The platinum-group elements (Os, Ir, Ru, Rh, Pd and Pt), which are the most valuable elements, are of strategic importance due to their growing use in advanced technologies and automobile catalyst converters. They have been described in a wide range of geotectonic settings, but the majority of the world supply of PGE is produced from magmatic ores derived from basaltic magmas. In most cases the PGE are associated with primary magmatic sulfides with interstitial textures to the silicate host. Major Pt and Pd economic mineralization is hosted in well-defined stratiform reefs of large layered intrusions, as is exemplified by the Bushveld Complex (South Africa), the Great Dyke (Zimbabwe) and the Stillwater Complex (USA). Zoned mafic-ultramafic igneous complexes of the Ural-Alaskan type are targets of Exploration and sources of significant economic platinum placer deposits as well.
The type of mafic-ultramafic complexes dominated in the Balkan-Carpathian system, is ophiolites associated with orogenetic zones. Although chromite is major collector of the platinum-group elements (PGE), their content in large chromite deposits is generally low (few hundreds of ppb). However, PGE-enrichment: (a) in all PGE, (b) only in Os, Ir and Ru or (c) in Pt and/or Pd, are a common feature of disseminated chromite and/or relatively small chromite occurrences, of both high-Cr and high-Al type, in the uppermost parts of the mantle and/or in the lowest crust sequence. Examples of PGE-enrichment include the ophiolites of Pindos, Skyros Island and Veria (Greece), Bulqiza and Tropoja (Albania), Dobromirtsi (Bulgaria) (Economou-Eliopoulos, 1996; Ohnenstetter et al., 1999). The platinum group minerals (PGM) may be precipitated directly from silicate melt (S-poor), immiscible sulfide liquids, and the magmatic volatile phases. PGM can be classified into two subgroups: the more Os-, Ir- and Ru-rich or IPGE (Ir-goup) and Pt, Pd-rich or PPGE (Pt-group) assemblages. The more Pt- and Pd-rich assemblages (Pd–Pt, Pd–Pt-alloys, Pt-arsenides, most likely sperrylite) occur interstitial to chromite grains. On the basis of field and experimental data small grains of PGM (average 25 μm) of the IPGE-goup, commonly laurite, as inclusion in unaltered chromite have been interpreted as an early magmatic phase formed by direct crystallization of a basaltic magma. The presence of members of the irarsite-hollingworthite solid-solution series and other Os-, Ir, Ru- and Rh-bearing PGM in PGE-enriched altered chromitites from some ophiolite complexes may indicate either in situ alteration or/and remobilization and re-deposition of PGE. A salient feature of the latter case is the presence of extremely large (over 1.3 mm) PGM grains and extremely abundant PGM small grains/fragment (over 100) dispersed along a highly fragment chromitite zone, in a distance over 3 mm. They occur within small chromite occurrences located along a shear zone of strongly brecciated chromite ore of Veria having high PGE (up to 25 ppm) content (Tsoupas and Economou-Eliopoulos, 2008). Such fluid-driven multistage platinum-mineralization and subsolidus reactions are considered to be widespread, but the system is considered to be a closed one with respect to PGE. The relatively high IPGE-enrichment in chromitites seems to be related to post magmatic processes covering a long period of deformation episodes, starting from the asthenosheric mantle flow (plastic deformation). Thus, most targeting locations in the Balkan-Carpathian system are (a) for the chromitite-IPGM associations exclusively small chromite occurrences along shearing zones of ophiolite complexes, postdating their initial/magmatic PGE deposition, and (b) for the PPGE the uppermost parts of the mantle and the lowest crust sequence.
Platinum and Pd contents in sea-floor massive sulfides are very limited. However, elevated contents, reaching values up to 1 wt % Pt in marcasite and chalcopyrite from massive sulfides on the East Pacific Rise, 1000 ppb Pd in sulfide deposits on the mid-Atlantic, and 1000 ppb Pt in disseminated pyrite and chalcopyrite from brecciated pipeform diabase, underlying the massive ore of the Pindos ophiolite complex (Greece) may indicate that Pt and Pd are quite soluble under a range of hydrothermal conditions (Economou-Eliopoulos, 2005and references there in). Traditionally PGE are associated with mafic-ultramafic complexes. Although porphyry deposits are major sources of Cu, Au or Mo, recently, in addition to gold the research interest has been focused on the Pd and Pt distribution in porphyry deposits because certain porphyry Cu-Au deposits have shown elevated Pd and Pt contents, reaching values over 5 ppm in high-grade bornite-chalcopyrite and/or flotation concentrates from Aurich (average ≥ 0.4 ppm Au) porphyry deposits in British Columbia and Colorado (Eliopoulos and Economou-Eliopoulos, 1991; Economou-Eliopoulos, 2005). Late Cretaceous to Miocene porphyry Cu deposits, extending from Romania, through Serbia and Bulgaria to Greece are the most important porphyry intrusions related to continental collision and post-collision magmatism.
The Pd-telluride, merenskyite, has been described as the main PGE mineral in porphyry Cu–Au–Pd–Pt deposits, such as Skouries, Elatsite, Medet and Bor/Madjanpek. Merenskyite occurs mostly as inclusions and at margins of chalcopyrite and bornite or forms intergrowths with Pd-Pt-Bi- and Ag-tellurides. The potential for PGE mineralization associated with such large Cu and Au-Cu porphyry deposits is still unknown. However, the average (Pd+Pt) values (over 5 ppm) are considered to be encouraging for Pd and Pt as by-products, with Au as a byor co-product, and porphyry deposits a good target for Pd & Pt exploration. Porphyry Cu-Au-Pd±Pt deposits of the Carpathian-Balkan system show some similarity in terms of their associations with alkaline rocks, in particular those characterized by (a) SiO2 <65 wt%, (b) a major contribution by crust material, as is exemplified by the 87Sr/86Sr and 207Pb/204Pb values, (c) their association with alkaline or K-rich calc-alkaline systems, characterized by relatively high of REE, Th and halogen (F, Cl) contents (d) the close association of the Cuminerals with the main Pd-bearing mineral, merenskyite, and Au–Ag tellurides, (e) the association of the elevated Pd, Pt, and Au contents with magnetite-bornite-chalcopyrite assemblages, and the pervasive potassic alteration type at the central parts of the deposits, and (f) the transportation of Cu and precious metals, as chloride complexes, by relatively hot (400-700°C) and saline to hypersaline (>70 wt% NaClequiv) hydrothermal fluids. Thus, critical factors controlling base/precious metal potential of porphyry Cu+Au+Pd±Pt deposits are considered to be the composition of parent magmas (contribution of mantle, oceanic and continental crust) and the physico-chemical conditions during the formation of porphyry Cu deposits. The oxidized nature of parent magmas, as is exemplified by the abundance of magnetite, may be related to the ability of producing hydrothermal system with ideal chemistry for transporting precious metal and represent good exploration target for the precious metals, whilst “reduced” porphyry Cu-Au deposits, lacking primary hematite, magnetite, and sulphate minerals (anhydrite), contain abundant pyrrhotite, and are relatively Cu-poor, but Au-rich deposits.
This presentation will review and interpret recent data on magmatic processes in the Carpathian – Pannonian Region (CPR) during Early Miocene to Recent times, and will compare them with contemporaneous magmatism in the Balkan Peninsula and the Aegean, all of which belong to the Eastern Mediterranean realm. This geodynamic system was controlled by the collision of part of Africa (Adria or Apulia) with Europe that generated the Alps to the north, the Dinaride-Hellenide belt to the west, and caused the extrusion and inversion tectonics in the CPR. The present-day tectonic configuration is a result of the Cretaceous to Neogene Africa–Eurasia convergence and collision that formed a complex lithosphere supplied with numerous subduction components. The CPR contains Neogene to Quaternary magmatic rocks of highly diverse compositions that were generated in response to complex post-collisional tectonic processes. These processes formed back-arc extensional basins in response to an interplay of compression and extension (e.g. subduction with roll-back, collision, slab break-off, delamination, strike-slip tectonics, core complex type extension, and block rotations) of two microplates: Alcapa and Tisia (Tisza)-Dacia. Competition between the different tectonic processes (syn- and diachronous) on both local and regional scale caused variations in the associated magmatism that were mainly a result of extensional processes, the rheological properties, and the specific lithosphere composition of the two microplates. No volcanic activity directly related to pre-collisional subduction is recorded in the CPR area. Meanwhile in the Balkans a regional extensional tectonic setting developed in Oligocene- Miocene times and progressed to the present-day in the Aegean where it was dominantly associated with calc-alkaline, ultrapotassic and Na-alkaline magmatism and formation of small sedimentary basins.
Major oxide, trace element, and isotopic data of lavas and mantle xenoliths from the CPR suggest that subduction components were preserved in the lithospheric mantle after the Cretaceous-Miocene subduction and were reactivated by asthenosphere uprise via various processes (subduction roll-back, rotation-induced extension, slab detachment, slab-break-off or slab-tearing). Changes in the composition of the mantle through time support various geodynamic scenarios that are linked to the evolution of the main blocks and their boundary relations: Alcapa (1), Tisia-Dacia (2) and Balkans (3):
1a. In the Western Carpathians and Pannonian Basin, magmatism occurred in a backarc setting producing felsic volcanic rocks at 21-18 Ma, followed at 18-8 Ma by felsic and intermediate calc-alkaline lavas and ended with Na-alkaline basaltic volcanism (10-0.1 Ma). Volcanism became younger towards the north. Geochemical data imply both a change in source from a crustal one, through a mixed crustal/mantle source, to a mantle source with a decrease of the subduction component in the mantle lithosphere through time. Garnet-bearing varieties occurred at 16.4-15 Ma. Extrusion tectonics, block rotation, subduction roll-back and continental collision triggered partial melting by delamination and/or asthenosphere upwelling. Generation of Na-alkaline magmatism at the western margin of Alcapa suggests a north-east-directed asthenosphere mantle flow acting as small finger plumes that caused high thermal anomalies at the base of the lithosphere and triggered magma generation along NWSE strike-slip faults. The process was most likely controlled by mantle perturbations resulting from the counterclockwise rotation of the Adriatic microplate and tectonic inversion in the Pannonian Basin. The continuous volcanic activity in central Slovakia, firstly as calc-alkaline (16.5-11 Ma), then as transitional calc-alkaline (11-8 Ma) and finally as Na-alkaline basalts (8-0.13 Ma) supports a mantle plume scenario, with increasing asthenospheric input through time;
1b. The westernmost Pannonian sub-basins (Styrian basin and adjacent areas) contain felsic and intermediate calc-alkaline, K-alkaline and ultrapotassic volcanic rocks generated at 17.5-14 Ma. They are related to extension and extrusion tectonics and core-complexgeneration at 21.9-13.4 Ma that produced strong mantle perturbations and triggered melt generation. Na-alkaline basalts occurred at 11-12 Ma and ended at 4-1.8 Ma. They show heterogeneous isotopic features that suggest an association with the Adria push and tectonic inversion, causing a north-east directed asthenospheric mantle flow;
1c. In the north-westernmost part of the Pannonian Basin, at 15-9 Ma, felsic and normal calc-alkaline volcanism erupted in the Transcarpathian basin at a triple junction between Alcapa, Tisia-Dacia and the European foreland. This is a result of extension via counter-clock rotation of Alcapa, causing core-complex exhumation. Geochemical studies indicate a heterogeneous lithospheric mantle source associated with fractionation-assimilation processes in crustal magma chambers. Melting was most likely triggered by back-arc rotational extension and asthenosphere uprise;
2a. Calc-alkaline magmatism generated at 12-8 Ma in the northern part of the Tisia-Dacia block follows the Dragoş Vodă-Bogdan Vodă transcurrent fault and is entirely intrusive, ranging from basalts to rhyolites. Each body evolved independently with specific fractionation, crustal assimilation and/or magma mixing processes, suggesting decompression melting of the local heterogeneous mantle lithosphere. Garnet-bearing varieties occurred at 9.5-10.5 Ma. Sinistral transtensional stress regimes at 12-10 Ma along the transcurrent fault system controlled the generation and emplacement of the intrusive bodies. This may be the result of oblique convergence of Tisia–Dacia with the NW–SE striking European margin, evidenced by eastward thrusting in the external Miocene thrust belt;
2b. Calc-alkaline and adakite-like magmas were erupted in the Apuseni Mountains at 15-9 Ma. Garnet-bearing rocks occurred at 13-12 Ma. Lithosphere breakup during extreme block rotations (~60 degree) at 14-12 Ma was responsible for extension with core-complex formation at the easternmost continuation of Bekes basin. This led to decompression melting of an enriched lithospheric source. Magmatic activity ended with small volume Na-alkaline basalts (2.5 Ma), shoshonitic (K-alkalic) at 1.6 Ma and ultrapotassic magmas at 1.3 Ma. This suggests a close relationship with Pliocene inversion tectonics along the South Transylvanian fault due to the Adria push, with small volume melt generation from diverse lithospheric and asthenospheric sources;
2c. Calc-alkaline magmatism occurred along the easternmost margin of Tisia-Dacia forming the Călimani-Gurghiu-North Harghita volcanic chain, with diminishing age and volume southwards at 10-3.9 Ma. This marked the end of subduction-related magmatism along the post-collision front of the European convergent plate margin. Magma generation was associated with progressive break-off of a subducted slab and asthenosphere uprise. Fractionation and crustal assimilation were typical;
2d. At ca. 3 Ma, magma compositions changed in South Harghita to adakite-like calcalkaline and continued until recent times (< 0.03 Ma) interrupted at 1.6-1.2 Ma by simultaneous generation of Na and K alkaline varieties in nearby areas, suggestive of various sources and melting mechanism. This complex magmatism situated in front of the Moesian platform was associated with two main geodynamic events: (a) slab-pull and steepening, with opening of a tear-window in the vertical Vrancea lithospheric block hanging into the asthenospheric mantle (forming adakite-like calc-alkaline magmas) and (b) inversion
tectonics along reactivated fault systems that allowed decompression melting of asthenospheric and lithospheric sources, thus generating the Na and K-alkaline magmas;
3a. Calc-alkaline volcanic rocks occur at the southern border of Tisia–Dacia with the Dinarides along the Drava–Sava depression in several successive periods between 22.8 and 7.4 Ma, with K-alkaline rocks at 17.5-15.4 and 9.8-7.4 Ma. The area acted as a strike-slip fault at the terrane boundary that was probably reactivated several times in transtensional mode, generating magmas via decompression melting of heterogeneous lithospheric mantle, also influenced by fractionation and assimilation;
3b. Miocene-Pliocene magmatism characterizes the Serbian and FYR Macedonian part of the Vardar zone. Ultrapotassic, shoshonitic and high K-calc-alkaline magmas were erupted at 23-21 Ma; at 12.9-10 shoshonitic rocks were generated and ended with K-potassic and ultrapotassic magmas at 9.1-1.5 Ma, becoming younger toward the south. Magmas were generated in a metasomatized depleted mantle related to different extensional events in the Pannonian Basin and Aegean region;3c. In the Thrace Evros basin, Early Miocene (22-19.5 Ma) calc-alkaline and K-alkaline rocks occur, suggesting an origin from both lithospheric mantle and crust related to postcollisional extensional processes and core complex exhumation. In the Thrace basin, Naalkaline basalts occurred at 8.9-4.5 Ma; decompression melting of an asthenospheric source may be related to a westward mantle flow generated by the block movement along the North Anatolian fault system;
3d. The South Moesian block has an N-S line of Na-alkaline basalts that started in the Oligocene and become younger toward the south at 21.4-19.4 Ma. They have an asthenospheric source that may be connected to local fractures related to Tisia-Dacia block rotation movements around stable Moesia. Thus, the mantle dynamics and melt generation in CPR and surrounding areas are echoes of many subduction, collision, rotation and extension processes of several microplates that acted variably in the convergence between Africa (chiefly Apulia) and Europe since the Cretaceous period until Recent time.
There is no plate tectonics modelling without local geological investigations, and a few square meters of well-dated radiolarian cherts can completely change a tectonic model. If ample geological information can be obtained from a given outcrop, the next step consisting in interpreting these in terms of geodynamic environment will often generate contradicting points of view. That is where the larger plate tectonics modelling will bring some constraints.
Most disagreements are rooted in 2D cross sectional approaches of local information, usually considering all the presently juxtaposed geological units as potential actors of a single geodynamic history. Plate tectonics modelling certainly helps in solving the exotic nature of a given unit, and it can be shown that large scale displacement of terranes is rather the rule than the exception.
This can be tested in the Pacific region during the last 250Ma. Terranes have been crossing this large expanse of water, colliding with each other, and then being re-dispersed from tropical to polar regions. Still, these processes are constrained through properly done local investigations. Similarly the Variscan terranes have experienced long distance travelling, from their peri-Gondwana position to their amalgamation along the Eurasian margin. Their final juxtaposition resulted from further displacement during the formation of Pangea. In this instance, the final juxtaposition cannot be used readily to decipher the wander path of these terranes, and only a well constrained plate tectonics model will offer a possible solution.
It is clear from our plate model that the European Variscan terranes occupied the whole border of Gondwana, from South China to South America. The different geodynamic settings along that margin allow defining the former location of the different terranes. The intra-alpine Variscan and Mediterranean terranes were located close to South China, the Iberian terranes were close to the Libyan-Egyptian part of Gondwana, and the Armorican terranes s.l. were located further west. The so-called Rheic margin of Gondwana experienced quite different geodynamic evolutions before the detachment of the Variscan terranes. This can be used as a guideline to put in place this amazing puzzle.
The western Tethyan realm is dominated by the closing of the Paleotethys and the concomitant opening of the Neotethys in the Permo-Triassic times. This process followed the assembly of Pangea and amalgamation of Variscan terranes. However, if continent-tocontinent collision took place from the Alleghanian N-American domain to the west Mediterranean area, further east (from Italy to the Middle East) the southern margin of Eurasia remained an active margin. This generated the opening of numerous back-arc basins along that margin from the Late Permian to Late Triassic. The continuing subduction of Paleotethys northward also generated slab pull forces that triggered detachment of the Cimmerian ribbon terrane from Gondwana in the Permian, as did the Variscan terranes in the Devonian.
In that respect the Variscan scenario is quite similar to the Cimmerian one, terranes detached from Gondwana collided with terranes derived from Eurasia, and finally the amalgamated terranes were squeezed between larger continental masses (Gondwana and Laurasia in the Carboniferous for the Variscan orogenic event, Africa-India and Eurasia in the Tertiary for the Cimmerian-Alpine event).
The eo-Cimmerian orogenic event, however, has quite distinct features. The collision was mainly Late Triassic in age corresponding to the final closure of the Paleotethys in Greece, Turkey, Iran, Afghanistan and further east. Jurassic Cimmerian events in the Balkan and Turkey were related to the closure of some Paleotethyan back-arc basins (Maliac, Küre) and to shortening in neighbouring areas such as the Caucasus. The final collision in these areas with larger landmasses occurred only in the middle Tertiary, so the delay between terrane accretion and final orogenic events was locally quite long (up to 200 Ma).
So, the Cimmerian collisional events must be regarded as separate from the Variscan and Alpine ones. The other main difference is that the Variscan terrane accretion was an arcarc collisional event, resulting in important HT type metamorphism, accompanied by large magmatic pulses related to mantle delamination. For the Cimmerian event, the collision was between a ribbon type passive margin and island arc type terranes, it resulted in soft docking with little metamorphism and magmatism, and limited orogenic processes. In areas where the Cimmerian suture can be studied in details, such as central Iran, the fore-arc series (arc side, upper plate) are found resting directly on the flexural bulge of the passive margin (lower plate), both separated by a few hundred meters of highly sheared flysch-like deposits. The lower plate is hardly deformed, the upper plate presents some imbrication and shortening, and the intervening accretionary prism has nearly completely disappeared, it was totally underplated.
Both upper and lower plates had been previously thinned due to rifting (separation of the Cimmerian terrane from Gondwana on one hand, separation from the Eurasian active margin by back-arc spreading on the other hand). Thus the superposition of both thinned plates in the Triassic did not create much isostatic rebound, and in some areas where the Cimmerian terrane was not very large, sedimentation continued during most of the Triassic, both on the lower plate side, and on the newly created passive margin of the back-arc, to the north of the orogenic zone.
This makes the Cimmerian event difficult to recognize in some areas. The suture zone was not very large, and in Greece and Turkey it hardly outcrops. However, this Late Triassic period was accompanied by widespread clastic influxes in surrounding basins, the Cimmerian collage being surrounded by oceans on its southern (Neotethys) and northern (Eurasian backarc) sides. Some of these clastic deposits contain olistostroms with blocks clearly pertaining to the disappeared Paleotethys (e.g. pelagic Carboniferous to Early Permian, totally absent outside of the Paleotethys). Some remnant flexural (molassic) basins are also known in Iran (Shemshak). In Turkey they were often interpreted as rift basins. However, a thorough study of the clasts in Late Triassic Turkish conglomerates has shown their exotic nature, and mainly their late Paleozoic pelagic characterictics, showing that they were derived from a suture zone and not rift related; they are commonly followed by a major stratigraphic gap.
In Greece, the remnants of the Cimmerian events are scarce, because of the lack of relevant outcrops. This situation is due to the fact that the final collision with a large landmass (i.e. Africa) has not yet taken place. The Cimmerian remnants are still underplated under the external Hellenides, and/or covered by large carbonate platforms. Our investigation during the last 20 years on this problem has brought to the light that most substratum of the external domain can be attributed to the Paleotethys Permian fore-arc domain, strongly affected by Triassic rifting (somehow quite similar to the present-day Aegean sea area) that led to the opening of the Maliac and Pindos back-arc basins. The latter ceased opening when the arc to the south of it collided with the Cimmerian Apulian terrane. However, the suture zone is not seen, or indirectly, because some Triassic conodonts found in the east Mediterranean basin (Neotethys) are not present in the Pindos north of it. A major barrier prevented these animals and few other species to pass from one basin to the next.
So, in conclusion, the larger geodynamic picture can be derived from the study of suture zones over a large area and from the evolution of margins on both sides of it, but in some areas, only pebbles or microfossils will lead to the solution. It is up to the geologists to use both approaches with some wisdom.
The Western Balkan region is a region of south-eastern Europe that presents pronounced activities of various types of natural hazards and natural disasters. This paper analyses data sets from two international databases of the main types of natural disasters namely geophysical, hydrological, climatological and meteorological disaster events during the period 1900-2008. The following have been analysed: the number of natural disaster events, natural disaster occurrence by disaster type, the total number of fatalities, the total number of affected people and the corresponding economic damages expressed as a percentage of selected types of natural disasters. The data analysis in this paper aims to confirm the importance of data collection and analysis аs а foundation for planning and preparing disaster reduction programs for the Western Balkan countries.
Temporal distribution of triggered seismicity following a strong earthquake has been the subject of many studies that focus on applying statistics to earthquake sequences. The earthquake occurrence can be described by stochastic processes and therefore probabilistic models are developed in order to assess the seismicity rate changes resulted after a strong event. The several statistical methods that serve this purpose are based on different assumptions. The seismicity rate changes during three earthquake sequences that took place in the territory of Greece are investigated. The first is the 1981 Corinth Gulf seismic sequence, with three strong (M=6.7, M=6.5 and M=6.3) events between February 24 and March 4, the second one the 2001 Skyros Island sequence, with the main shock occurring on July 26 with M=6.3, and the last one the 2003 Lefkada Island, with a main shock of M=6.2 occurring on August 14. An attempt is made for modeling the aftershocks, as they comprise a major portion of an earthquake catalog including important information about the rate changes. Firstly, a homogeneous Poisson model is tested to fit the data, with the waiting times of the point process being exponentially distributed and the rate λ of the Poisson process constant in time. The process has no memory and any particular event is regarded as unrelated to any other. Substituting a function λ(t) for the rate λ leads to a non–homogeneous Poisson process with intensity function λ(t). In this case the rate parameter is time dependant and the appropriate form of the function has to be chosen in order to describe the way seismicity rate evolves with time. In the present work two forms were tested, both allowing the rate decaying as time passes. The first one is an exponential function with two unknown parameters, whereas the second one is a non-homogeneous Poisson process with a Power Law intensity function λ(t). Because of the rate’s form the particular model is also known as a Weibull process. The third statistical method applied to the data is the Autoregressive model of second order (AR(2)), which is used in time series analysis to describe stationary time series, and is a linear regression of the current value of the series against two previous values of the series. In order to apply the AR model to the above earthquake sequences, a random variable Z(t) was considered to represent the number of earthquakes at any time t and the parameters of the model were estimated using the Yule–Walker equations.
The ruin of the medieval Sasov castle, a cultural heritage object in the Middle Slovakia, suffers from a strong deterioration. Besides the weathered binder, a reasonable part of the damages is caused by the intensive weathering of the building stone. The walls are builtmainly of Neogene andesite, which is common in this area of the volcanic Stiavnicke Vrchy Mts. The sound rock is of dark grey colour, but most of the building stones have yellowishbrown coatings of iron oxyhydroxides on the surface and in the fissures. Highly macro-porous stones are most affected by the alteration. Weathering of the andesite was studied within the project VEGA 1/0413/09 of the Ministry of Education of the Slovak Republic.
The X-ray diffractometry (XRD) of the powdered weathered building stone showed that the mineral assemblage is dominated by the plagioclase andesine (63 wt%) and the main alteration product smectite (up to 22 wt%), the rest are amorphous phases/volcanic glass (13 wt%), augite (1 wt%), magnetite (1 wt%) and traces of mica. The building stone material was compared with the rock material from an old local quarry, which was assumed to be the source of the building material for the castle walls. The study with polarized light microscopy (PM) of thin sections revealed the glomeroporphyritic character of this rock, i.e. phenocrysts of the same type (here plagioclase) are partly grouping into distinct clusters. There are three types of plagioclase: 1. sound plagioclase with regular shape and typical crystal twinning, 2. phenocrysts exhibiting growth zoning, and 3. plagioclase disintegrated due to magmatic corrosion. The corrosion creates alteration rims around the plagioclase grains or intrudes the whole mineral. A secondary mineralisation can be seen in some fine cracks cutting the phenocrysts, as well. The alteration of mafic minerals (augite, magnetite, mica) resulted in opaque phases. The rock matrix is built of volcanic glass, fine-grained plagioclase and some not identified brown phases. These are probably products of a post-magmatic alteration, i.e. weathering and/or post-volcanic hydrothermal alteration processes, very common in Neovolcanites.
The results from XRD, PM and tests on physical properties confirmed a very good match of the building stone material with the most altered parts of the rock mass in the local quarry. Therefore, a comparison with the sound rock from the deeper parts of the quarry was used for the illustration of the alteration impact on the rock properties. The sound rock consists of andesine (≈ 62 wt%), the rest are amorphous phases (27 wt%), augite (8 wt%) and magnetite (3 wt%), no smectite is present. It means that amorphous phases are the most unstable components of the rock. With the alteration, smectite appears and its content is increasing (up to 22 wt%), while amorphous phases, augite, and magnetite are decreasing. A considerable part of the macro-pores is the result of selective leaching of weathering products. Total porosity increased from 2.4 % to 21.2 %, the effective porosity from 2.2 % to 15.0 % when compared with the sound rock. The uniaxial strength (tested by the point load test) dropped from 270 MPa (sound rock) to 51 MPa in the weathered, but still coherent macroporous stone. However, the most altered building stones are almost white and disintegrate into sand. Cyclic volume changes due to smectite swelling and water freezing in the effective pores probably weaken the structure and enhance the deterioration. Both processes are supported by the high water uptake due to the high smectite content, reflected also in the results of the Enslin-Neff tests. Therefore, ruins should be prevented from the infiltrating water precipitations (rain, snow) by roofing of the wall crowns. Missing or deteriorated building stones could be replaced by material taken from the deeper parts of the local andesite quarry.
The geological map of the Caucasus and adjacent areas of 1:2 500 000 scale, being presented on the 19th Congress of the CBGA includes on-shore and off-shore parts of the Black Sea-Caspian Sea region (Fig. 1). Small-scale thematic (geologic, tectonic, metallogenic, etc.) maps of th World and its large parts, such as Europe, Middle East etc., have been periodically compiled and published under umbrella of the Commission for Geological Map of the World (CGMW), for example: carte geologique de l’Europe, 1:10 000 000, 1970; carte tectonique de l’Europe et des regions avoisinantes, 1:10 000 000, 1975; carte tectonique internationale de l’Europe et des regions avoisinantes, 1:2 500 000, 1980; geological map of the Middle East, 1:5 000 000, 1986; 1:5 000 000 International geological map of Europe and adjacent areas, 2005, BGR Hannover; the international geological map of the Middle East, 1:5 000 000, second edition, 2009-2010. The Caucasian region, situated at the junction of the European and Asiatic segments of the Alpine-Himalayan orogenic belt and serving as a connecting link between these two branches, as a rule, is illustrated by maps of the both segments. The presented map demonstrates up-to-date level of knowledge on geological structure and evolution of the region.
The first results regarding the Early Pleistocene Teleostean marine fish fauna of the Faliraki area (Rhodes Island, Dodekanese) are presented as revealed through the study of fish otoliths. In the Faliraki Bay section outcrops the Rhodes Formation, consisting of Kritika Member, Kolymbia Member, and Lindos Bay Clay Member, both now assigned to the Early Pleistocene. Fish otoliths have been found within the Kolymbia and Lindos Bay Clay Members.
Significant is the first record of the modern species Notoscopelus bolini Nafpaktitis 1975 in the Kolumbia Member of Faliraki Bay section. N. bolini resembles the N. elongatus elognatus which has been recorded in various localities of the Western and Central Mediterranean, but has a greater postero-ventral width. The Faliraki specimen also shares a lot of characters with N. resplendens of Nolf & Cappetta from the Neogene sediments of SE France may also be attributed to Notoscopelus bolini. This species has been recorded in the Mediterranean Sea since the Tortonian, and today it occupies the central – eastern Atlantic Ocean and the Mediterranean Sea. It is a temperate pelagic – oceanic species, which exhibits a maximum abundance between 45-50 meters modern sea depth. Important also is the presence of the Lampadena aff. urophaos atlantica Maul 1969 in the Early Pleistocene deposits of the Kolymbia Member, which has previously only been recorded in the Middle Pleistocene bathyal deposits of Vallone Catrica section. The modern distribution of this species is restricted to the North Atlantic. It is a bathypelagic species which occupies water depths between 60 m and 1000 m.
The sediments of the Lindos Bay Clay Member of Faliraki Bay section reveal a very rich otolith association. The great majority of specimens belong to the Myctophidae family, with representatives namely Ceratoscopelus maderensis Lowe 1939, Diaphus holti Taning 1918, Diaphus rafinesquii (Cocco 1838), Diaphus taaningi Norman 1930, Hygophum benoiti (Cocco 1829), Hygophum hygomi (Lutken 1892), Lobianchia dofleini (Zugmayer 1911), Electrona risso (Cocco 1829), Notoscopelus sp., Myctophum punctatum Rafinesque 1810, Benthosema glaciale (Reinhardt 1837) (very scarce and small otoliths only), Lampanyctus crocodilus (Risso 1810), and Scopelopsis pliocenicus. Present are also members of the family Gadidae, such as Gadiculus argenteus Guichenaut 1850, as well as Gobiidae. The Teleost fish assemblage of the Lindos Bay Clay Member is composed of an abundant and diversified pelagic group and to a lesser degree by a benthopelagic and benthic group. This type of fauna generally characterizes the continental slope environment, with the depth usually exceeding 200 meters. This is in good agreement with the estimations of 300-600 meters in the lower part of the section to 200-300 meters near the top, as provided through the study of the bryozoans associations in the Lindos Bay section.
The studied Pb-Zn-Cu deposits are located between Çanakkale and Balıkesir in NW Anatolia. Two ore deposits are investigated here, in Lapseki-Çataltepe to the northwest and in Yenice-Kalkım to the southeast of Çanakkale. The host rocks in both areas are represented, from the bottom to the top, by lense- and/or band-shaped recrystallized limestones, and/or marble-intercalations bearing Permo-Triassic metamorphic rocks. Eocene granitoids and subvolcanics are found in Lapseki area, whereas Oligo-Miocene aged granitoids and Middle Miocene subvolcanic rocks are found in Yenice area. The Pb-Zn-Cu mineralizations in these areas are observed at and around the carbonates and along fractures in the metamorphic rocks. The sulfide minerals comprise mainly galenite, sphalerite, chalcopyrite, pyrite and arsenopyrite, whereas the gangue minerals in the ore zones are represented by garnet, epidote, quartz and calcite. In addition to these minerals, manganiferous hedenbergitic pyroxene and hematite have been detected in the ore zones of Kalkım area.
Fluid inclusion studies of Kalkım area (Handeresi, Bağırkaç and Fırıncıkdere mineralizations) revealed that fluids in pyroxenes have salinities of 5.4 to 8 wt.% NaCl equiv., and the homogenization temperatures (Th) range between 290 and 430°C. The salinities of sphalerites are around 11 wt.% NaCl equiv., and the Th vary from 272 to 338°C. The fluids during quartz formation stand out with the salinities of 1.4 to 2.6 wt.% NaCl equiv., and Th of this stage is 157-267°C. On the other hand, the Th of the fluids during calcite formation ranges between 68 and 75°C. The salinities of this stage could not be measured. The fluid inclusion measurements of Lapseki area (Çataltepe mineralizations), showed that the fluids in garnets have salinities of 0.7 to 1.4 wt.% NaCl equiv., and their Th range between 310 and 353°C. Sphalerites have salinities of 0.5 to 1.2 wt.% NaCl equiv., and Th of 220 to 300°C. The salinities of fluids related to the quartz formation vary between 0.5 and 1.1 wt.% NaCl equiv., and their homogenization temperatures from 200 to 310°C. Because the system was open, based on the fact that both liquid and gaseous phases could be observed at the same fluid inclusions in both areas, sphalerite homogenization temperaturescould be evaluated as formation temperatures varying between 220 and 340°C.
In Kalkım area, the sulfur isotope compositions of the sulphide minerals are: δ34SPbS = -1.1 to 1.5 ‰ with a mean around -0.2 ‰, δ34SZnS = -0.7 to 2.1 ‰ with a mean around 0.7 ‰, and δ34SCuFeS2 = -0.6 to 1.5 ‰ with an average around 0.4 ‰. The sulfur isotope composition of the sulphide minerals in Lapseki area are characterized by δ34SPbS = -0.5 to 0.0 ‰ with an average around -0.25 ‰, δ34SZnS = 0.8 to 1.3 ‰ with a mean around 1.03 ‰, δ34SCuFeS2 = 0.9 to 1.5 ‰ with an average around 1.2 ‰, and δ34SFeS2 = 0.0 to 1.0 ‰ with a mean around 0.5 ‰. The δ34S values of sulfide minerals in both areas show a narrow range near 0 ‰ which can be interpreted as indicating magmatic sources and the sulfur isotopes are very similar to δ34S values of skarn deposits.
The Apuseni Mountains of Romania contain a large number of precious metal deposits, many of which are epithermal in character and closely associated with calc-alkaline, Miocene volcanism. These magmatic rocks which host the mineralization have recently been subjected to several detailed geochemical and isotopic studies and our understanding of their genesis and evolution is now fairly well-developed. However, in spite of the detailed mineralogical studies which have over the years been carried out on the mineral deposits, there are still many aspects about their formation which are poorly understood. The timing of the mineralization in particular is not well defined, and so a geochronological study using K-Ar and Ar-Ar methodology and focussing mainly on the mineralization at the classic Sacaramb deposit, was initiated.
In order to check the published K-Ar ages of fresh, host magmatic rocks, two Ar-Ar ages for amphibole were obtained (from Zuckerhut, Sacaramb, and Rovina Remetea, near Brad). The ages of these rocks (Ar-Ar 11.2 and 15.2, compared to published K-Ar ages of 10.9 and 15.2 Ma respectively) appear to conform the validity of the K-Ar technique for these magmatic rocks.
There is a general lack of minerals in the mineralized veins which are suitable for age dating. However, hydrothermal alteration selvedges to the mineralized veins contain K-mica (sericite) and K-feldspar and these have been analysed and used as a proxy for the metallic mineralization. K-Ar ages of sericite from veins in the Sacaramb area are in the range 9.9-10.8 Ma, whilst the ages of host rocks in the near vicinity are in the range 10.9 and 11.2 Ma. Hydrothermal K-feldspar from Hondol gives similar ages of 10.6 Ma (K-Ar) and 9.8 Ma (Ar- Ar), compared to the K-Ar age of the host rock of 10.8Ma. A K-Ar age of sericite from Magura of 11.1 Ma is slightly younger than a K-Ar age of the host rock of 11.5 Ma. Ar-Ar analyses of sericitic mica tend to give apparent ages which are 1-3 Ma older than the K-Ar ages but it is at present unclear whether these are real or a result of the analytical method (argon recoil in fine-grained mica samples). These results also suggest that earlier attempts at dating the alteration using Rb-Sr isochrons are probably inaccurate.
The mineralization in this region occurred at a roughly similar time to that proposed by previous studies in the Baia Mare region of northern Romania. The ages of the Apuseni mineralization appear to be slightly younger than the ages of the host volcanic rocks, although this difference is usually within the analytical uncertainty of the analyses (typically <1 Ma), and there is no confirmation of perceived gap in time between mineralization and volcanism seen at Baia Mare (0.5-1.5+ Ma). Although there is quite a large span in age for the volcanism of the Apuseni Mountains as a whole (7.4-14.9 Ma) these age data indicate that the associated hydrothermal activity (and thus most likely the mineralization also) was directly linked to the immediate, host magmatic rocks, was fairly short-lived, and took place within a limited time interval after the cessation of volcanism.
The results of a detailed trend analysis of surface longwave and shortwave radiation over Europe are presented on a basis of data from the ISCCP project (International Satellite Climatology Cloud Project). The ISCCP FD SRF dataset includes spatially and temporally homogenized up-welling and down-welling longwave (LW = 5.0-200.0 microns) and shortwave (SW = 0.2-5.0 microns) radiation estimates coming from the synergistic use of satellite data and models. The area of interest, Europe, consists of equal area grids with a spatial resolution of equatorial 2.5x2.5 degrees (280 km2). The temporal resolution of the data is 3 hours while the dataset spans from January 1984 to December 2007. In order to study the long-term variations of the longwave and shortwave radiation, monthly mean values of the above mentioned period were considered. A statistical analysis is applied to derive trends and seasonal variability for this time period over Europe. To fit the time series, a model with a linear trend and a seasonal component for the annual cycle of radiation has been used. The seasonal component is estimated by a harmonic analysis. The significance of the longwave and shortwave radiation trend is also determined. As it is shown here, the observed trends and their significance are rather variable for different areas in Europe.
Late Miocene-Pleistocene alkaline mafic magmas were erupted in the Carpathian-Pannonian Region following the Eocene to Miocene subduction-related calc-alkaline volcanism. The lavas range from hy-normative basalts through alkali olivine basalts andbasanites to nephelinites.
The majority of basaltic lavas are fresh, olivine-phyric and holocrystalline, whereas olivine is coupled by clinopyroxene phenocrysts in some samples. The olivine phenocrysts contain occasionally spinel inclusions. The matrix consists of plagioclase, clinopyroxene and olivine along with titanomagnetite, ilmenite, and apatite. Phlogopite, interstitial alkali feldspar, nepheline and leucite also occur in some of the lavas. In contrast, nephelinites are rich in clinopyroxene and nepheline and contain titanomagnetite in the groundmass along with subordinate amounts of olivine, apatite and leucite.
Olivines mg-numbers vary between 88-66. They are generally zoned and began to crystallize with Fo around 87 and 79. In the course of crystallization Fo decreases to 84-66 at the rims of phenocrysts being similar to Fo in the groundmass. The NiO of the olivines decreases with decreasing MgO content, while CaO and MnO increase.
Clinopyroxene compositions range from augite to diopside. They exhibit both oscillatory and sector zoning as a result of disequilibrium crystallization. The compositional difference between cores and rims follow the normal pyroxene fractionation trend; the cores are richer in Mg, Si and Cr and poorer in Fe, Mn and Ti than the rims. The majority of the clinopyroxenes have AlVI/AlIV (0.0-0.65) typical for low pressure clinopyroxene and support shallow level crystallization.
Most alkali basalt corresponds to the criteria for primitive rocks having high mgnumber (>0.62), high MgO (>9 wt. %) and high Ni (>192 ppm) and Cr (>286 ppm). These magmas underwent only minor olivine±clinopyroxene±spinel fractionation and apparently approach a primary melt composition.
The silica saturation index (vary from -59 to +2) and trace element ratios (LaN/YbN=11-31) generally suggest that these lavas have experienced different degrees of partial melting. The hynormative basalts of Oberpullendorf have the highest degree of melting while Stradnerkogel nephelinites have the lowest. Those rocks that formed via a low degree of melting possess high Zr/Hf ratios (60-66), and negative K and Ti anomalies similar to those of carbonatites. All studied rock varieties have high Nb/La ratios (>1) suggesting OIB-like asthenospheric mantle source. The absence of LILE enrichments (K, Rb and Ba) indicating no interaction with fluids possibly derived from subducted slab. The steep REE patterns and the high DyN/YbN ratio (average 1.8) strongly suggest that garnet was a residual phase during the partial melting in the source region.
The 87Sr/86Sr isotopic compositions of the studied lavas are low (0.703505-0.704279), and the 143Nd/144Nd ratios are high (0.512736-0.512858). Thus, they are isotopic depleted relative to the bulk Earth and similar to HIMU-OIB. Moreover, they are similar to those of Romanian basalts and Neogene alkali basalts throughout Europe.
In the geotectonic unit of the External Dinarides, several volcaniclastic-sedimentary successions of Middle Triassic age have been investigated from outcrops in Croatia (in the vicinity of Sinj and Knin) and in Bosnia and Herzegovina (in the vicinity of Bosansko Grahovo). The appearance of volcanic and volcaniclastic rocks in the External Dinarides have usually been interpreted as the Middle Triassic syn-rift phase in which graben-like depressions had been formed along deep structural fractures. The Middle Triassic rift phase in the External Dinarides is marked by volcanic activity that had been defined as basaltic extrusions at the beginning and more acidic explosive activity that characterised deposition of thick pyroclastic and volcanoclastic successions in the later phases. Volcanic and volcaniclastic successions near Sinj have been described mineralogically and petrographycally by the same authors and interpreted as vitric to crystal tuffs and ignimbrites deposited as pyroclastic flows in intrashelf environment, not far from a subaerially located caldera.
In our investigation we examined several lithotypes of volcanic and volcaniclastic rocks not previously described. Near Bosansko Grahovo there are occurrences of blocky pepperites. In the angular pepperite type jigsaw-fit texture can be observed suggesting quenching of Mgdepleted basaltic lava on the contacts with unconsolidated pelagic limestones. The Ladinian age of the succession was determined on the basis of conodonts found in limestones intercalations.
Near Sinj a thick volcaniclastic beds (called “pietra verde”) are interbeded with marine bioclastic, well bedded limestones, cherts and dolomites. Bioclastic limestone and dolomites are characterised by an abundance of calcareous algae, foraminifers, gastropods, bivalves, brachiopods, crinoids, serpulids as well as radiolarians, ammonoids and conodonts, the latter suggesting open marine (pelagic) associations. Limestone beds are strongly silicified and recrystalised. Dolomites exhibit macrocrystaline anhedral texture suggesting a secondary dolomitisation. Lower Ladinian age was inferred on the basis of conodonts and amonoids.
Volcaniclastic beds (tuffs) near Sinj are massive or evenly laminated. Cross lamination occurs at the top of some beds. Several volcaniclastic lithotypes (tuffs) do not significantly differ in composition. They contain predominant former glassy fragments which are cuspate, platy, or udeformed bubble-wall shards. Pumice wisps occur in some lithotypes showing random orientation and relict tube vesicle texture. Other components are sparse feldspar and quartz crystal fragments. The formerly glassy shards are recrystalised to a fine quartz-rich mosaic. Shards are occasionally well preserved due to carbonate microcrystaline calcite that outlines them.
The dominance of juvenile pyroclasts, particularly the abundance of various shard types and quartz crystal fragments suggest that they were sourced from explosive, acidic eruptions. The interlayering with carbonates containing pelagic (open marine) fossil assemblages suggests that they have been deposited farther offshore. In this circumstances are these subaqueous deposits not likely to by strictly primary pyroclastic in origin. Bedforms indicate rapid, possibly mass-flow, deposition in offshore environment. Nevertheless the abundance of texturally poorly or unmodified pyroclasts suggests that pyroclastic material was delivered more of less directly to sedimentary transport and deposition systems. Although it has been suggested that the origin had been primary pyroclastic surge deposits from subaerial depositional settings, we thought that pyroclastic material generated from explosive eruptions at marine submerged vents. The dominance of juvenile pyroclasts suggests that fragmentation occurred when lavas emplaced into marine unlithified sediments allow explosive vaporisation of pore fluids or when superheated water flashed to steam that rapidly expands. Thus we interpret deposits near Sinj as pyroclast rich offshore mass-flow deposits.
Rapid development of geopark concept and positive results of existing geoparks have generated in Romania both the official recognition of geopark as distinctive protected area and the increase of interests of new territories to develop geoparks. Based on a local initiative and a grass root effort a new geopark project has been launched in Romania: The Buzău Land Geopark. Located in the south-eastern part of Romania, the territory covers about 1100 sq kilometers, comprises 18 mayoralties and a population of 45000 inhabitants. Unique geological sites like mud volcanoes, amber deposits, salt caves, and oil springs are present. Sedimentary rocks folded and overthrusted outline a geological history covering more than 70 million years. The paper presents the main steps taken so far in building the new geopark. The approach is based on our previews experience in Hateg Geopark and in other geoparks members of the European Geoparks Network. The process comprises: interdisciplinary research studies, stakeholders identification, local heritage evaluation, and sustainable development strategy design, establishing the basic requirements for a brand development, correlation with local projects and initiatives and design of training courses for the geopark team. This approach allowed us to identify the optimal territory for the geopark, to create a framework for partnership, local needs identification and to set-up clear objectives for sustainable use of local resources. The commitment of local communities has generated national projects dealing with public awareness, cultural events, promotion, and informal education. All these are valuable elements to prove the rightness of the geopark concept and its capacity to join around groups and stakeholders from different areas of interest.
The Devonian sequence of the Moesian Platform in Bulgaria and Romania represents a part of the pre-Variscan sedimentary cover which overlies the Proterozoic metamorphic basement. A total of sixteen boreholes have been run in different parts of the Devonian.
The Lower Devonian, together with the Silurian, consists of dark shales, siltstones, and minor limestones and sandstones (calcareous-terrigenous-clayey formation). The age assignment of this formation is based on chitinozoans, acritarchs, miospores, graptolites, and conodonts.
Predominantly carbonate rocks (limestones and dolostones) and rare evaporites (anhydrites) build the Middle and Upper Devonian successions. They were subdivided into the following formations from bottom to top: carbonate-sulphate formation, dolomite formation, formation of banded limestones, formation of intraclastic and peloidal limestones, and formation of organogenic limestones. The lower clayey-carbonate package of the carbonate-sulphate formation consists of clayey limestones and shales of Eifelian age and the upper parts of this unit consist of Givetian dolostones, limestones, anhydrites, and scarce shales. The dolomite formation includes mainly dolostones and limestones, also of Givetian age. The formation of banded limestones consists of banded micritic limestones related to Upper Givetian and Lower Frasnian. The uppermost part of the Devonian is represented by the formation of intraclastic peloidal limestones (Frasnian-Famennian) and the formation of organogenic limestones (Famennian). The Middle and Late Devonian ages of these formations were mostly proved by conodont faunas and less commonly by brachiopods and foraminifers. Sedimentary features and conodont evidence indicate the presence of numerous erosional surfaces and stratigraphic hiatuses within the Middle and Upper Devonian carbonate sequence.
The silicicalstic sediments of Silurian and Early Devonian age (calcareous-terrigenousclayey formation) are regarded as formed in deep-water open-marine to shallow shelf settings. Middle Devonian successions are interpreted as inner- and mid-ramp deposits developed in a shallowing-upward sequence. Eifelian carbonate sedimentation (clayey-carbonate package of the carbonate-sulphate formation) occurred in an open-marine setting below normal wave base (mid-ramp zone) which is gradually replaced by a shallow open-marine environment above normal wave base (inner-ramp zone). The shallowing tendency continued during the Givetian when carbonate-evaporite sediments precipitated under arid climate conditions (carbonate and evaporite packages of the carbonate-sulphate formation). Deposition took place in a low-energy tidal-flat setting (back ramp) with restricted or semi-restricted water circulation and locally developed supratidal sabkha evaporites. Repeated alternation of subtidal, intertidal, and supratidal successions observed in the well sections suggests a cyclic character of the Givetian sedimentation. Tidal-flat deposition continued later during the Givetian and Frasnian (dolomite formation, formation of banded limestones and formation of intraclastic and peloidal limestones) but without distinct evaporite precipitation. However, carbonate pseudomorphs after gypsum crystals observed in some intertidal/supratidal sediments indicate that arid climate conditions still existed. Finally, the Famennian carbonate deposition (part of the formation of intraclastic and peloidal limestones and the formation of organogenic limestones) reflects a gradual transition to open-marine shallow and deeperwater settings.
With the final of the carbonate sedimentation in the Early Carboniferous, the whole Devonian underwent intense folding, vertical and horizontal displacement as a result of the Variscan orogenic events.
Asprogerakata section, located in the northeast part of Levkas Island, Ionian Sea, consists of well-bedded grey-brown calcareous sandstones and silty to sandy marls and represents part of the Miocene transgressive cover of the Ionian zone. Biostratigraphic data and palaeoenvironmental conditions are inferred based upon the planktonic foraminifera. A rich, highly to moderately diverse and well preserved planktonic foraminiferal association enabled biostratigraphic zonation of the Lower-Middle Miocene deposits. On the basis of the composition of the foraminiferal assemblages, palaeoecological and palaeoclimatic interpretations have been made. Quantitative and qualitative analyses provide a detailed distribution of the identified taxa and defined a number of bioevents for the Middle Miocene. The recognition of the first Acme End (AaE) of Paragloborotalia siakensis proved that the Neogene deposits in Levkas Island have an age of 15.435 Ma and belong to the MMi4 planktonic foraminiferal zone. The MMi4c-MMi4d boundary has been defined by the presence of Praeorbulina glomerosa circularis dated at 14.89 Ma. Planktonic foraminiferal assemblages identify a significant change in variability of climate system at around 15.2 Ma, probably corresponding to the global cooling events superimposed to the Middle Miocene Climatic Optimum. In particular, faunal composition suggests a warm phase in the lower part of the section followed by a cooling phase.
Our recent research in most areas of Eastern Hellenides has given following results:
In Vourinos and Vermion, the ophiolites are in normal, not tectonic contact with their supporting layers (marbles of mostly upper Triassic age). This contact shows a typical thermal transformation with layers of hornstein, amphibolites and granatites. The directly underlying series shows progressive and clear evolution from a carbonate platform into a submarine environment with increasing volcanic influences, including pillow lava flows.
In northern Pindos, at the ophiolitic overthrusted masses, outcrops of limestones are observed. Detailed analysis of these limestones showed that they are remainings of transgressions, their age determined by the microfauna as upper Campanian – early Maastrichtian. The limestone series ends upwards in a karstic surface supporting doleritic lava flows with essential thickness. In the locations of Tragopetra and Tzina we can observe that these lavas clearly intrude in the caves of the paleokarst. At the same section, over this lava formation can be found the basic conglomerate (Auversian) of the ''mesohellenic trench'' sediments. An important outcome of this is that there is no ocean floor before the overthrust but that land, with karstification of the limestones, was already emerged instead.
In central Pindos, near Artotina, we observe ophiolite outcrops in the Pindos flysch with a transgression enclosing microfauna of the same age.
In Euboea, a ''subpelagonian'' ophiolitic unit, with his underlying limestones, is overthrusted over a paleozoïc and mesozoïc continuous sedimentary succession (Eretria unit), but the contact is violently folded and characterized by a thick mylonite. This Eretria unit is the equivalent in South Euboea of the Styra unit and is overthrusted over a continental platform carbonate unit (Almyropotamos unit).
In Argolide, we observe the same situation: an ophiolite unit, overthrusted over limestones and flysch with a mylonitic contact, with insertions of klippes of a continental slope unit (Pindos). Localy, the limestones are karstificated before the overthrust.
As a conclusion of these observations we can state that we should respect the principle of actualism (James Hutton, Charles Lyell). Now, in present world, the geographic zones are large, extended: so was also in the past. The distinction of a (paleo) geographical zone must be based on the trend through geological times, not on local variations of sedimentation. Today, we observe a breaking up of geological units, due to more successive tectonic phases, not to a primary differentiation. Like this, already in Middle Cretaceous or even earlier, Tethys’s floor (ophiolites with effusive emplacement) was deformed and at least folded, and emerged. This emersion possibly characterizes also certain parts of African shelf. Immediately afterwards, ophiolites overthrust on the African shelf in an enormous movement, which drifted, fragmented and disintegrated the continental slope (Pindos unit, Eretria unit). This movement is accompanied also by proportional movement of the European-Asian mass. It is deformed in the scale of planet. It is obvious that this major movement was immediately followed by a phase of strongly, isoclinal folding, trending from SSW to NNE. The most obvious today (because latest) deformation during Late Eocene and Oligocene is the one which caused the actually observed main structural lines of the Hellenides.
Greece's geology favours a potent and dynamic use of mineral resources, which became a major incentive of the country's mining business, and economic and social growth. Among the Non-Energy Metallic Minerals commodities, base and precious metals, in particular zinc, lead, copper, gold, and silver are becoming an increasingly important and rapidly growing target of the mining industry. In NE Greece, where most of the potential resources and feasible deposits are hosted, gold-base metal mineralizations occur in a wide range of genetic types comprising magmatic, hypothermal/mesothermal, epithermal, and supergene mineralization types. The magmatic porphyry copper type deposits and mineralizations show economic gold grades (e.g. Skouries, Fisoka, and Pontokerasia), the hypothermal/mesothermal manto-type base metal sulphides form high-grade gold ores (e.g. Olympias, Mavres Petres, Piavitsa, Thermes, Pangeon, Farasino) and the epithermal gold systems lead to potential high-sulphidation mineralizations (e.g. Konos, Perama, Kirki, Pefka). Proven reserves amount to porphyry gold and copper of 3.9 Moz and 0.8 Mt, respectively, mantotype gold of 3.6 Moz, lead + zinc of 1.6 Mt and silver of 66 Moz, as well as more than 2.0 Moz epithermal gold. The genetic link between porphyry coppers and large base metal manto style sulphide deposits can be incorporated into regional exploration strategies in a complex metamorphic terrain of schists, gneisses and marbles, whereas the epithermal type deposits were emplaced within a broad volcanic belt, which developed first in Bulgaria and then moved south through northern Greece to the region of Thrace. The epithermal gold mineralization occurs in hydrothermal breccia zones, related to volcanic rocks of andesitic, dacitic or shoshonitic composition as well as hosted by sedimentary rocks. All previous types of sulphide minerals (particularly those hosted by Rhodope and Serbo-Macedonian marbles) were overimposed by post-Pliocene co-active supergene oxidation and karstification processes (e.g. Angistro, Menikio). All the main types of gold mineralization are linked to plate tectonic movements during the Tertiary. From the global metallogenetic point of view
the post-Alpine Tertiary geodynamic systems in SE Europe are potential in producing highgrade ore deposits of base and precious metal sulphide minerals.
Early Miocene (ca. 21-18 Ma) volcanic activity in the Kulu (Konya)-Haymana (Ankara) area produced a series of lavas and pyroclastic deposits with calc-alkaline and mildly alkaline affinities. The volcanic products display a broad range of compositions from basic to acidic (48-72 SiO2 wt%). The calc-alkaline volcanic rocks include plagioclase (An27-60), clinopyroxene (Wo40-44En41-50Fs8-17), orthopyroxene (Wo1-4En64-76Fs20-35), amphibole (Mg# = 0.63-0.77), Fe-Ti oxide, quartz, apatite, and scarce biotite whereas the mildly alkaline rocks contain plagioclase (An41-74), olivine (Fo64-89), clinopyroxene (Wo41-48En39-50Fs7-16), orthopyroxene (Wo2-4En65-74Fs23-33), amphibole (Mg# = 0.59-0.69), Fe-Ti oxide, apatite, and scarce anorthoclase. The rocks generally show disequilibrium textures such as: (a) resorption, oscillatory zoning, honeycomb and sieve textures in plagioclase phenocrysts, (b) amphibole phenocrysts pseudomorphed by opaque aggregates and surrounded by clinopyroxene corona, (c) composite pyroxene phenocrysts with core of orthopyroxene (enstatite) and rim of clinopyroxene (augite), (d) quartz surrounded by acicular clinopyroxene, and (e) reverse zoning in all phenocrysts. Estimations of pre-eruptive temperature (T) are in the range of 810- 1120 oC for the calc-alkaline and 1055-1300 oC for the mildly alkaline rocks. Estimations of crystallization pressure (P) range between 1.0-7.5 kbar for the calc-alkaline and 1.9-8.6 kbar for the mildly alkaline rocks, suggesting polybaric fractionation history. Textural and compositional relationships of mineral phases and P-T conditions of the rocks suggest that magma mixing played an important role in the evolution of the investigated volcanic rocks.
Dating radiolarites overlying ancient oceanic crust preserved in the Lesser Caucasus is of key importance to understand the geodynamic evolution of the greater area between Eurasia and the South-Armenian Block, a micro-continent detached from Gondwana during Late Palaeozoic–Early Mesozoic time. Micropalaeontological data are few and/or obtained before the development of a modern taxonomic framework for Mesozoic Radiolaria.
Two main ophiolitic zones are recognized in the Lesser Caucasus and they are linked to the evolution of Tethys: 1) the Sevan-Akera zone, situated in the East and SE of Lake Sevan, constitutes the main suture zone of Neo-Tethys ocean in the Lesser Caucasus, and 2) the Vediophiolitic unit, in the SE of the capital city Yerevan, is considered as a folded klippe sequence thrusted on the South-Armenian Block. We focus here on biostratigraphic results obtained recently on the sedimentary cover of the Sevan ophiolite, considered to have been formed in a low spreading back-arc oceanic basin. Amongst the various localities studied, three yielded identifiable radiolaria. Radiolarian assemblages obtained from the Sarinar section allow to investigate the sedimentary and volcanic history recorded in an ca. 30 m-thick radiolarite sequence associated with spilitic lavas of the Sevan ophiolitic suture zone. Three distinct Radiolarian assemblages were recognized and they establish that the studied sequence is tectonically reversed. The younger assemblage can be assigned to the Unitary Association Zones (U.A.Z.) 19-22 of Baumgartner et al. (1995) and correlated with the Early Hauterivian/late Barremain to early Aptian interval, based on the co-occurrence of species “Sethocapsa” (?) orca, Tethysetta boesii and Hiscocapsa uterculus. The latter two species last occur in the lower Aptian Verbeeki subzone of O’Dogherty (1994). The intermediate assemblage is Late Jurassic in age (middle Oxfordian to early Tithonian; U.A.Z. 9-11), based essentially on the presence of Zhamoidellum ovum. Finally, the oldest assemblage may be correlated with the late Bajocian-early Bathonian, based on the presence of “Tricolocapsa” sp. M sensu Baumgartner et al. 1995. Several tuff levels are intercalated within the Upper Jurassic part of the radiolarite sequence. They are the evidence for a subaerial volcanic activity that took place in the oceanic realm of Tethys preserved in the ophiolites of Sevan-Akera zone.
In the Dali section, radiolarites overly spilitic lavas and are intercalated with tuffites. The co-occurrence of Cinguloturris cylindra and Emiluvia pessagnoi multipora allows the assemblage to be correlated with the Late Tithonian-Berriasian (U.A.Z. 12-14). This age proves that oceanic crust was being formed at the Jurassic/Cretaceous transition being accompanied by subaerial volcanic activity.
At the locality Tsegnaged, situated north of the town Sevan, two chert samples associated with lavas yielded Early Cretaceous radiolarian assemblages: the first can be assigned to U.A.Z 13-17 (latest Tithonian to late Valanginian) based on the co-occurrence of Archaeospongoprunum patricki and Obesacapsula cetia, while the other to U.A.Z. 18-22 (latest Valanginian/Hauterivian to early Aptian) based on the presence of Aurisaturnalis carinatus perforatus.
A Triassic Silicic Volcano-Sedimentary (SVS) succession is part of the Circum-Rhodopes Belt in Northern Greece. It records the voluminous rhyolitic activity that occurred on a Paleozoic composite basement (united Vertiscos plus Pelagonia terranes) at the early stages of extension that ended in continental break-up, separation of the above two terranes and creation of the Almopias Ocean. The SVS succession stratigraphically overlies the alluvial fan deposits of the Permo-Triassic Examili Formation, sourced from the eroded Vertiscos terrane, and is overlain by a Neritic Carbonate Formation of Triassic age. It comprises pyroclastic rocks, lava flows and quartz-feldspar-phyric intrusions, as well as epiclastic volcanic, non-volcanic and mixed volcanic – non-volcanic sediments, all now metamorphosed in low greenschist facies.
The Nea Santa rhyolite dome is part of the SVS succession and is exposed in the Xiropotamos Creek between Nea Santa and Krithia villages. The dome is ~1000 m across and includes four facies recognizable despite their metamorphism and deformation. These are: (a) the “coherent rhyolite facies”, representing the core of the dome and consisting of massive, non-vesicular quartz-feldspar porphyry, locally flow-banded; (b) the “lithophysal rhyolite facies”, occurring in parts of the periphery of the dome. It is perlitic rhyolite porphyry containing spherulites weathered out from the host rock. Each spherulite contains a quartzfilled, star-shaped internal cavity (lithophysa); (c) the gradational “carbonate sediment matrix – sericite-altered rhyolite breccia facies”, defining the original contacts of the dome with carbonate sediments of the Neritic Carbonate Formation. It is composed of fluidal, ragged clasts and stringers of sericite-altered pumiceous rhyolite enclosed in bio-calcirudite host sediment (reef-debris). It is interpreted as intrusive hyaloclastite or fluidal peperite, based on criteria like: hydrothermal metamorphism of the host sediment adjacent to rhyolite clasts (bleaching, silicification and calcite recrystallization) and fluidization of the host sediment (calcite-filled vesicles in rhyolite clasts); (d) the “carbonate sediment matrix – quartz-feldspar porphyry breccia facies”, occurring as dyke-like breccia zones that range from 5 mm to 50 cm in width and penetrating the western part of the dome. It comprises blocky, angular, in places jigsaw-fitted porphyry clasts enclosed in carbonate host sediment. It is interpreted as blocky peperite intruded into dome’s open fractures formed at its last, brittle stage solidification. Some clasts were also spalled from the sides of the fractures. A relatively younger facies, named “mixed rhyolite – carbonate epiclastic sedimentary facies” was formed adjacent to the dome. It consists of rounded quartz-feldspar porphyry and carbonate clasts (granular siltstone, pebbly granular siltstone and pebble conglomerate). It is interpreted as mixed provenance mass- and debris-flow deposits.
The Nea Santa dome displays typical characteristics of domes formed in submarine successions. During emplacement, its margins were quench-fragmented and mingled with wet unconsolidated carbonate sediment forming intrusive hyaloclastite (fluidal pepperite). The pumiceous nature of the fluidal hyaloclasts and the lithophysal nature of the periphery of the dome imply volatile exsolution not inhibited by the confining pressure, implying further that the sediment cover above the dome was thin and the water depth probably less than 200 m. The host carbonate sediment composed of reef-debris indicates that the dome intruded in a shallow submarine environment, below wave-base. The dome finally reached above storm wave-base level and was at least partly extrusive. Its fragmented margins were subjected to reworking and were syn-deposited with carbonate clasts on its flanks below wave-base as mixed provenance gravity-driven debris- and mass-flows. The identification of peperitic or intrusive hyaloclastite margins of the Nea Santa dome within the SVS succession is decisive for the relative chronology, facies architecture and palaeoenvironmental reconstruction because its presence demonstrates approximate contemporaneity of rift magmatism and sedimentation.
The Vitosha volcano-plutonic edifice crops out in the western part of the Srednogorie structural zone. The plutonic body is composed of abyssal gabbros and anorthosites, hypoabyssal monzonites, syenites and late veins of granosyenitic composition, intruded in Late Cretaceous volcano-sedimentary sequence. Volcanic rocks are represented by basaltic andesites and andesites.
The major rock-forming mineral phases are plagioclase, K-feldspar, amphibole and clinopyroxene. Common accessory minerals include apatite, titanite, magnetite, ilmenite and zircon. Secondary minerals are epidote, tourmaline, chlorite, actinolite, adularia and clay minerals.
Plagioclases span much of the crystallization history throughout the magmatic series, generally decreasing in anorthite component from basic to acid plutonic varieties. In volcanic rock the plagioclase is in the bytownite–labradorite range.
Potassium feldspar of orthoclase composition is typical for the monzonite and syenite. It forms large crystals, disposed between plagioclase. The orthoclase is the major carrier for Sr, Ba, Pb, Rb.
Amphibole is the main mafic mineral in all rock types, with Mg# 58-97. In the classification diagram of Leake et al. (1997), the amphibole from the plutonic rock falls in the field of the magnesio hornblende and ferrohornblende, whereas the amphibole from the volcanic rocks is tschermakite.
Clinopyroxene is a characteristic mineral for all rock types with Mg# 58-84. It forms deep resorption nuclei or single grains with euhedral contours. Compositionally it is augite and diopside.
U-Pb single zircon method was used for the precise geochronological dating of the Vitosha volcano-plutonic edifice. Sr and Nd whole rock and Hf–zircon tracing have been used to clarify the origin of the studied rocks.
Following U-Pb single zircon age data have been obtained for the plutonic rocks: gabbro 81.58±0.23, monzonite 82.45±0.4 and syenite 79.67±0.76. U-Pb data of single zircon grains from an andesite plot on a discordia with a Paleozoic age.
Strontium isotope data are quite variable, ranging between 0.7044 and 0.7042 in the less evolved gabbro and andesite, through 0.7052 in the monzonite, to 0.7091 in the syenite. Nd (80 Ma) values also show a large variation, from 0.37 to 2.74.
The new age data reported here provide that the rocks of the Vitosha pluton range between 82.4 and 79.7 Ma. Chemistry of the parental magma suggests similarity with the other plutonic suites from the axial part of the western Srednogorie. Compositional variations of the rock-forming minerals indicate calc-alkaline I-type signature for the Vitosha pluton. Sr and Nd isotope data indicate the presence of depleted mantle source for the parental magma, whereas generation of most evolved magmas requires different degree of crystal contamination. The upper discordia intercept U-Pb zircon of Paleozoic age suggest that the contaminant must have been lithologies from the Variscan basement.
A new locality tracked down in the Eurotas Valley (Laconia, Greece) yielded mammalian dental remains of a young individual referred to as Hippopotamus antiquus. The findings are of very large size compared to already known specimens from Greece and W. Europe. The new locality is biochronologically dated at the Early–Middle Pleistocene.
Neogene/Quaternary deposits along the east shoreline of Thermaikos Gulf (Thessaloniki, Greece) occasionally yielded several isolated fossil vertebrate remains. A proboscidean tusk and an equid astragalus have been recently unearthed from a new palaeontological spot near Epanomí. The finds are referred to Mammuthus cf. meridionalis and Equus sp. On the basis of biochronological data the deposits are dated as latest Pliocene.
A large-scale Vertical Electrical Sounding (VES) survey was conducted at the basin of Sarantaporon, Elassona in order to study the tectonic and hydrogeological setting of the area. More than 150 soundings (AB/2 > 500m) were measured on a near-regular grid and were processed with 1-D inversion algorithm. Selected Interpretation models took into account the existing detailed drilling information of the area. Since some of the dense measured soundings were co-linear was possible to combine 1-D sounding data and produce 2D data sets which were interpreted using a fully 2D inversion algorithm. Finally the 2D and 1D results were combined to produce pseudo-3D geolectrical images of the subsurface.
Interpretations are in very good agreement with the existing drilling and geological information and reveal a relatively detailed picture of the basin’s lithological and hydrogeological environment. Further, the results allowed us to obtain new, and verify existing, structural information regarding the studied area. Overall it is concluded that advanced interpretation to 1-D VES measurements can produce improved subsurface geophysical images and presents a very useful tool for larger scale geological investigations.
The Meliata Unit is crucial for understanding the West Carpathian geology. Its remnants mark an important suture zone which remained after the Meliata part of Neotethys Ocean which was open in the Middle Triassic and partly closed in Late Jurassic time. The key areas, in which occurrences of this unit are concentrated, are near Meliata village and in the wider surrounds of Margecany and Jaklovce villages. The first site lies southwest of the Gemeric Superunit, whereas the second occurs at its NE margin. Position of the Meliata Unit on the both sides of this crustal block (comparable with Greywacke Zone of the Eastern Alps) led some authors to oppinions about two branches of the Meliata Ocean surrounding the Gemeric Superunit, whereas others inferred that the northern occurrences do not represent a true suture but they were transported to its recent position tectonically by thrusting (obduction). If the first oppinion was true there would be some time difference between the closures of the two branches. Therefore, the two principal sites, Meliata and Margecany were revisited and new micropaleontological data were obtained, the first report of which is given herein.
Margecany (the type outcrops of radiolarite-basalt succesion along the railway at the local cement factory were sampled)
In a red cherty limestone intercalated in the basalts, Triassic radiolarians (together with some poorly preserved conodonts (similar conodont fauna was previously found here by Kozur & Mock) with a mixture of some Jurassic ones, were extracted by dissolution. Microfacies of most of the reddish cherty limestone to radiolarites, is evidently Triassic. From a reddisch cherty limestone to radiolarite overlying the basalts, following radiolarian fauna was extracted: Actinomma cf. siciliensis, Crucella squama, Crucella spp., Hagiastrum sp., Paronaella pygmaea, Praeconocaryomma spp., Spongotripus sp., Elodium cameroni and Hsuum parasolense. The assemblage indicates Middle Jurassic age (Aalenian to Bajocian with two species; Callovian to Oxfordian indicated by one species). Estimation of the exact stratigraphic position is problematic due to the actual knowlegde of the age range of the species.
Meliata (the type locality of the meliata Unit)
Late Middle Jurassic matrix between the olistostromes and slide blocks of the upper part of the succession has already been investigated. The Lower part of the section was interpreted as a continous Anisian to Carnian sequence. A sample from the basal part of the section below the Ladinian cherty limestones and radiolarites and above the Anisian limestones yielded Higumastra winteri, Dictyomitrella cf. kamoensis, Stichocapsa cicciona, and Zhamoidellum cf. ovum. The assemblage indicates the Callovian to Early Oxfordian age. A sample taken higher, but still in the basal part contained Sethocapsa cf. kodrai indicating late Middle Jurassic. Microfacies of the samples represent radiolarian bearing filament limestone (resembling silicified Bositra limestone with radiolarians). In the upper part of the Meliata type section occur several grey limestones and dolomites in a late Middle Jurassic mélange. Besides Carnian limestones also Norian grey limestones occur representing typical components which were derived from the grey Hallstatt facies (Pötschen sequence in the Eastern Alps).
The studied samples all contain Jurassic or mixed Triassic-Jurassic fauna which is in accordance to the mélange character of the Meliata Unit with Triassic/Jurassic blocks and Middle to early Late Jurassic matrix. However, no new constraints concerning the time difference between the southern and northern occurrences of the Meliata Unit are possible.
The studied area is located in Hungary, one of the deepest parts of the Carpathian Basin. Körös Rivers (it means Fekete-, Fehér-, Kettős-, Sebes-, Hármas-Körös) is belonging to Tisza river drainage basin that is the second main watercourse in the country. The Körös catchment area is 27,537 km2, but 53% is in Romania, and 47% is in Hungary. Vast areas of the Hungarian Plain were flooded by the Paleo-Tisza and its affluents; and the river itself had not fix bed. The settlements were threatened by the enormous flood hazards returning year by year. The flood control has a long history in Hungary, because barrages were already built in 1613 along Tisza and other rivers. The real work started (with mapping) when a big flood was happened in the Körös–Berettyó region, in 1816. The Körös river regulation plan was made by M. Huszár, who distributed the work, and gave the depth and width of the bed, barrages distance and dimension. He determined the width of the active floodplain: by Hármas-Körös 379 m, by Kettős-Körös 246 m, by Sebes-Körös 246 m, by Fekete-Körös 190 m, by Fehér-Körös 114 m. The river regulation of the Danube and Tisza, and their affluents, was the most important reform in the remaking of nature in the 19th century Europe. These impacts were filled the requirements of the era’s economic and social assumption. Low and a high water level database were made for the time interval between 1907 and 2006 with two water gauges in case of analysing the regime of Hármas-Körös River. The low water level had occurred in winter time (57%) in Gyoma (first water gauge), the lowest was -116 cm on 3rd August in 1930. The highest water level had happened in the first five month of the year. The highest water level was 918 cm on 9th July in 1970. The biggest difference was 943 cm in 1919. In Kunszentmárton (second water gauge) the lowest water level had happened in winter time (69%) as well, and the lowest water level was -240 cm on 24th August, 1946. The highest water levels occurred in January, March, April, and May. The highest water level was 1041 cm on 21st April, 2006. The biggest difference was 1134 cm in 2006. We are dealing with measurements of alluvial deposits of floodplain, as well. The sampling was made at the Hármas-Körös River in Takács-zug. The aim of the study to find out the amount of flood deposits on the floodplain after the river regulations. Geomorphological mapping was made near Kunszentmárton and Öcsöd in scale 1:10 000. The new map demonstrates some paleodrainage system of the study area. The thickness of alluvial deposit is increased with 150–180 cm after the river regulations on the study area. The greater part of mapped area is high floodplain; a low floodplain is deepening into this, which was perhaps a fossil riverbed. This low floodplain was occupied by Körös River. The deposits of the last few year of the 20th century could be easily recognized; it is 5–13 cm by floods.
Studies performed in the last decade have shown the importance of geological sources in releasing methane, an important greenhouse gas, following only to carbon dioxide in the ranking of global warming producing gases. The IPCC Fourth Assessment Report, released in 2007, for the first time considers the geologic source of methane beside the other natural sources taken into account in the previous reports.
Mud volcanoes are important methane releasing geological features, occurring onshore and offshore in many parts of the world. Most of them are located in compressional settings, although in some cases they may be found in other tectonic environments. Most commonly, the onshore mud volcanoes are cone-shaped, with variable dimensions, from a few meters in diameter and less than one meter in height, to several kilometres in diameter and hundreds of meters in height. The shape of the mud volcanoes depends on the nature of the expelled fluids. Convex shapes are formed when the mud is viscous, but very frequently, circular pools with muddy water occur when the mineral fraction/water ratio is very low. In Europe, mud volcanoes are distributed in some specific areas. Such features were identified in Italy, Romania, and their occurrence continues eastward on the northern shore of the Black Sea (Ukraine, Russia), and in the Caucasian – Caspian area, where the world’s most impressive mud volcanoes were described.
The most important Romanian mud volcanoes are located in Berca area (Carpathian Foredeep), close to the bending zone of the Carpathian chain. These mud volcanoes are distributed in four distinct areas: Paclele Mari, Paclele Mici, Fierbatori, and Beciu, and seem to be the biggest in Europe, excepting the giant structures in Azerbaijan. In Transylvania, quite numerous methane releasing structures were identified. The mud volcanoes here are generally small, not exceeding a few meters in height and tens of meters in diameter. In some spots, dry gas emissions occur.
In the past years, the methane flux was measured by using the classical closed chamber method. After the chamber deployment, gas samples were collected by syringes and analysed in the laboratory by gas chromatography. Recently, an innovative measuring method was introduced by using a portable methane and carbon dioxide fluxmeter. Specific sensors for the two gases are connected to the accumulation chamber, and after deploying the device in the field, the gas concentrations are measured and fluxes derived. This new method has been used until now in Transylvania and a total flux of about 680 t CH4y-1 was estimated for theinvestigated areas in the Miocene basin of Transylvania. The total methane flux in Berca area is exceeding 1000 t CH4y-1.
Acknowledgments. The work described in this report was financially supported by the Romanian National Authority for Research (ANCS) within the Project 31-094 FLUX.
The project “SACRE” is based on the achievement of a health record from Chambord castle and aims to provide a basis for scientific monitoring and planning of restoration work using health and aesthetic specific criteria. The collected data (nature of degradations, weather measurements, architectural and historical archives) are used to reference all the information necessary to establish a detailed diagnosis of the state of alteration of the monument.
This program of research both fundamental and applied is divided into 5 parts:
1. The CAD modelling aims at constructing a graphic base used to gather all data acquired during the project.
2. The realization of the health record of the book will reference all the information necessary to establish a detailed diagnosis of the state of alteration of the monument: mapping of degradations, weather conditions, architectural and historical archives.
3. The simulation and prediction of degradations, which is the most fundamental step of this research program, is to simulate both in sequences of experimental laboratory and in numerical modelling the process of degradations in order to understand their evolution and to estimate their kinetics.
4. The creation of a tool for decision support is the application of simulation to work, and aims to estimate the rate of degradation. Added to that a costing of restoration, this software tool will provide a rational schedule of restoration work.
5. The valuation of the project to the public will be achieved by giving an access to a simplified version of the software, presented at an exhibition at Chambord.
The castle has undergone many restorations and architectural changes that have resulted in replacement of stones. Dating and identification of rocks were determined by searching in the historical and architectural archives that are sometimes incomplete. In developing the health record of the castle, we aim to identify and localize all the stones used over the time since the sixteenth century for the construction and for the restoration.
The ‘tuffeau’, porous chalk-lime and with very low mechanical strength, is the stone most commonly used in construction of buildings in the Loire Valley. It was also used for construction and restoration of the castle of Chambord. Stones used in the sixteenth century from quarries that are no longer used today. Over the successive restorations, new quarries have been opened.
The objective of this study is to identify geographically the various careers that have served the construction and restoration of the castle of Chambord, and locate the different stone facades employed. Indeed, these stones juxtaposed on the building are not always compatible. Correlating these data with the changes observed on the walls can give indications about the evolution of alterations observed on the chateau.
The paper presents results of calculation of the following elastic parameters: compressional wave velocity (VPEQ), shear wave velocity (VSEQ), velocity ratio VPEQ/VSEQ, acoustic impedances for either wave (AIPEQ, AISEQ), and bulk density (RHEQ). Elastic parameters were calculated for different lithostratigraphic series from fourteen selected boreholes from the Western Carpathians for which results of the quantitative interpretation of well logs were available. The analyzed area is located in the Polish Carpathians between Bielsko-Biała and Nowy Targ.
Those series contain Precambrian, Cambrian, Devonian (Lower, Upper and Middle), Carboniferous (Lower and Upper), Triassic, Jurassic, Cretaceous, Miocene and Paleogene rocks. The calculations were made for very different lithology, which was characteristic for those stratgraphic series, with the use of the Estymacja computer program written by Maria Bala and Adam Cichy within the research project No 8 T12B 046 20.
The idea of the method of estimation of P-waves and S-waves elastic parameters was based on known theoretical models (e.g. given by Biot-Gassmann or Kuster-Toksöz) relations which describe multiphase media corresponding to rocks with granular structure (grains: solid phase) filled with pore saturating medium (liquid phase, gas phase, solid phase). Elastic parameters of rocks are a resultant of all phase components: rock matrix and medium, and depend on relationships between components of the rock medium and isotropy or anisotropy of the rock skeleton.The computer program ESTYMACJA, allows elastic parameters of the rocks to be determined from results of integrated analysis of well logging data i.e. lithology, porosity and water, gas and oil saturation in the flushed zone or virgin zone. In our calculation the theoretical Biot-Gassmann’s model was used.
Those calculations were made for rocks in the A – 3 well, Ch -1 well, D – 6 well, J – 2k well, L-3a well, L - 7 well, R - 3 well, Ś – 1 well, W – 6 well, W – 1 well, W - 3 well, W-4 well, Z – 1 well.
Averaged values of estimated velocities VPEQ and VSEQ, VPEQ/VSEQ ratio, acoustic impedances (AIPEQ, AISEQ), and bulk densities RHEQ for each stratigraphic units together with lithology description were used to create a generalized set of parameters for groups of nearest wells or boreholes situated at the same profile. However, due to great variability of rocks belonging to different lithostratigraphic units, only the results from the nearest wells were compared.
The characteristics of VPEQ and RHEQ variability was performed for selected wells and stratigraphic series. One can observe a great variability of studied parameters, even for the same series and the same lithology. Results of estimated elastic parameters and bulk densities, presented in this paper, characterize a rock model with much varied litostratigraphy.
The East Rhodope Depression situated in South Bulgaria is a Paleogene superimposed structure. It is mostly filled with Tertiary sedimentary, sedimentary-volcanogenic, andvolcanic rocks. The tectonic low-order elements distinguished in it are specific volcanotectonic, block, and block-fold structures. The subjects of our study are the aquifer layers (reservoir systems) situated in these structures investigated from the point of view of the possibilities, if other favorable conditions for storage of natural gas and carbon dioxide (СО2) exist. Special studies carried out by the authors in the limits of the perspective structures are concentrated mostly on the: lithological-physical segmentation of the Tertiary section; defining of permeable and hard-permeable formations and their studying (structure, lithology, reservoir and sealing parameters, spatial behavior); defining of natural reservoirs and studying their spatial relationships; prognosis of possible types of local structures and natural traps. Because of the restricted volume and the absence of specialized information for a number of important geological preconditions and parameters, prognostic assessments are made with the use of indirect data, based on the contemporary ideas about the geological evolution of the examined region. Such are the structural-tectonic, the seismotectonic and the hydrogeological (hydrochemical, hydrodynamic) and the thermo-baric conditions. The prognoses concerning the perspectives for storage of natural gas and СО2 are related to the sunken areas within the Dzhebel and Krumovgrad depressions.
The Bakony-Balaton Highland Volcanic Field (BBHVF) is located in the central part of Transdanubia, Pannonian Basin, with over 50 alkali basaltic volcanoes. The volcanism was related to the post-extensional tectonic processes in the middle part of the Pannonian Basin. The basanite plug of Hegyestű erupted in the first phase of volcanic activity. It overlies Triassic limestone and dolomite forming a double hill. Since there is no clear evidence of explosive eruption history, Hegyestű is likely either a remnant of a dominantly lava emitting volcanic vent, or remnant of a lava derived from some sources nearby.
Ar/Ar [1] and K/Ar [2] ages were published on the alkali basalt rocks of the BBHVF. Conflicting K/Ar (5.97 ± 0.41 Ma, isochron) and Ar/Ar (7.78 ± 0.07 Ma, isochoron, 7.94 ± 0.03 Ma, plateau) ages were measured on the leucite-bearing basanite of Hegyestű. As it has been shown, this effect is caused by the special Ar retention feature of leucite in this basanite.
In a new study 18 K/Ar ages were measured on subsamples of HT-4 and on its fractions produced by magnetic and heavy liquid separation.18 K/Ar ages measured in the usual way were 25 – 45 % younger, but after HF or HCl treatment of the rock, or after reducing the baking temperature of the argon extraction line from 250 °C to 150 °C, they became similar to the Ar/Ar ages.
HCl treatment dissolved olivine, nepheline, leucite, magnetite and from 1-1 sample analcime or calcite. K dissolution studies on 6 samples from different locations of Hegyestű have shown that K content is mostly ~2 %, but it may decrease to ~0.3 %. HCl treatment dissolved 19 – 32 % of the rocks, 28.0-63.5 % of the K content, reduced the K concentration of the residue to 1.1 – 0.3 %, and for the dissolved part of samples with ~2 % K, the calculated K concentration was 4.02 – 6.42 %. These data and EMP analyis suggest leucite is the responsible mineral for the low temperature loss of 40Ar(rad) during baking the extraction line, though a minor role of nepheline can not be excluded.
Ar may release at low temperature from very fine-grained mineral, or when the Ar release mechanism changes. A 40Ar(rad) degassing spectrum has been recorded in the 55 – 295 °C range by stepwise raising the baking temperature and the data were plotted in the Arrhenius diagram. The arrangement of points proves very great change of Ar release properties in the 145 – 295 °C temperature range. This infers that Ar release is caused by a low temperature process, the change of the mineral structure of chemistry. Using the method presented here 7.56 ± 0.17 Ma, regarded as minimum age and similar to the Ar/Ar isochron age (7.78 ± 0.07 Ma) is determined for Hegyestű.
The result presented here point to the importance of checking the suitability of leucitebearing rocks for K/Ar dating, and simple methods are given for this control.
Reconstruction of the mantle flows within the mantle is essential for understanding of the Earth evolution. A temperature and pressure increase in the mantle causes phase transitions and related density changes in its material. The transition boundary in the pressure–temperature phase diagram is determined by the curve of phase equilibrium. If the slope is nonzero, a phase transition in hot ascending and cold descending mantle flows occurs at different depths and, therefore, either enhances (gamma>0) or slows down convection (gamma< 0). Endothermic phase transition at a depth of 660 km in the olivine partially slows down mantle flows. The mantle material has a multicomponent composition. Therefore, phase transitions in the mantle are distributed over an interval of pressures and depths. In this interval, the concentration of one phase smoothly decreases and the concentration of the other increases. The widths of phase transition zones in the Earth’s mantle vary from 3 km for the endothermic transition in olivine at a depth of 660 km to 500 km for the exothermic transition in perovskite, and the high-to-low spin change in the atomic state of iron takes place at a depth of about 1500 km. We present results of calculations for 2D and spherical models, demonstrating the convection effect of phase transitions as a function of the transition zone width. Transitions of both types with different slopes of the phase curve and different intensities of mantle convection are examined. The mixing of material under conditions of partially layered convection is examined with the help of markers. We analyze 2D and 3S mantle flow models with strong viscosity variations and phase transition to investigate this joint effect. For 2-D models we employ the generalized Moresi method. The 3S models are calculated with the CITCOM code.
Hamehkasy-1 and Korkora-1 are two iron deposits in Western Iran. Hamehkasy iron deposit is situated in the Sanandaj-Syrjan zone. It consists of two major economic indices and several sub-economic minor indices. Hamehkasy-1 is the largest index and is located to the north of Hamehkasy-2 at distance of 400 m. This ore body is being exploited at present. Korkora-1 iron deposit is located in the Oromieh-Dokhtar volcanic belt. It is one of ten indices in the Shahrak mining district. This ore body is the largest deposit in the area. Magnetite is the main ore in these deposits, but hematite, pyrite and goethite are present, too. For study magnetite in these ore bodies we used ore microscopy, EPMA and XRD methods. X-ray powder-diffraction data were obtained using: magnetite (Mg0.04Fe2.96O4), hematite (Fe2O3), quartz (SiO2) are common minerals, on records from Hamehkasy-1 samples we report magnesioarfvedsonite ((Na,K)3(Fe,Mg,Al)5Si8O22(F,OH)) for the first time in this deposit. In Korkora-1 samples the common minerals are: magnetite (Fe2.92O4), hematite (Fe2O3), goethite (Fe+3O(OH)), clinocholore ((Mg,Fe,Al)6(Fe,Cr)4O10(OH)8), and hydrohematite (Fe2O3,xH2O). Ore microscopy studies: in these studies we found magnetite in Hamehkasy-1 deposit which consists of high exolution but in Korkora-1 exolution in magnetite is rare. Magnetites in samples of each deposit were characterized by (EPMA) studies.
Camptonite dykes, 20 cm to 2 m wide, occur at the northern part of the Ditrǎu Alkaline Massif [DAM] (Eastern Carpathians, Romania), intersecting granitoids, syenitoids and hornblendites. Based on their low SiO2 and high alkali, TiO2, LILE and LREE content, high Yb/Nb, Ti/V, (La/Yb)N ratios, Zr/TiO2 vs. Nb/Y distribution, nepheline and olivine normative composition they are defined as silica- and alumina-undersaturated, alkaline basic rocks and basanitic in composition. The Mg#, Cr, Ni, Co and Sc concentration, and low S.I. and high D.I. values of the DAM camptonites indicate that they could be fractionates of primary melts. Based on strongly incompatible trace element composition the DAM camptonites derive from an OIB mantle source containing HIMU and EM I mantle components. The high LREE and low HREE content of the DAM camptonites (La/Yb=15-24) may indicate both a metasomatised mantle source for the magma generation and a garnet lherzolite source by very low degrees (~1-2 %) of partial melting. The latter mean that the camptonite magma must have originated at a great depth, around 60-80 km.
Mesozoic radiolarian biochronology has been essential in the understanding of the timing of formation and emplacement of remnants of ancient ocean basins in the Alpine-Mediterranean orogens. The first descriptions and biochronologic assessments of radiolarian faunas of the late 1970ies in the Helledides and Dinarides depended on biostratigraphic calibrations from Deep Sea Drilling Sites and on the first zonations established in Western North America, that were not adequate for the area. In the early 1980’s, as the first European Jurassic-Cretaceous radiolatian zonations were established, the dating of radiolarian-bearing sediments associated with basalts and ophiolitic mélanges became possible. The age assignments have been continuously refined since. The discovery of Triassic radiolarites associated with MORB-like basalts in the late 1980’s considerably changed the interpretations. Now, a wealth of biochronologic work has been published in the last 3 decades. For this report we have revised data from NW-Croatia, Serbia, Albania, Northern Greece, Othris, Evvia, Argolis, in an attempt to produce a coherent picture of all this data.
Radiolarian biochronology established in oceanic sediments associated with ophiolite belts in the Dinarides and Hellenides reveal 3 age clusters: Middle to Late Triassic, Middle Jurassic and Late Middle to Late Jurassic. Early Jurassic ages are extremely rare. Triassic ages have been found in oceanic sediments, chiefly radiolarites, associated with MORB-like and within-plate basalts, while the majority of Middle Jurassic ages have been found in sediments associated with basalts that geochemically are related to an intraoceanic convergent margin setting. Middle Jurassic radiolarites and radiolarian mudstones are also associated with ophiolite mélanges that are allochthonous with respect to the continental margins. Late Middle to Late Jurassic ages are found in synorogenic deepwater pelagic and ophiolitebearing detrital sediments that stratigraphically overly marginal series. These deposits formed during the obduction of the ophiolites onto the adjacent continental margin. Exposure/erosion and emplacement of the ophiolites is largely diachronous along the Pelagonian-Korab-Durmitor margin and in part synchronous with an ongoing formation of Vardar (suprasubduction) oceanic crust. Westward younging of ophiolite detritus on the Pelagonian margin implies an eastern (Vardar) origin of the ophiolites in Eastern Greece.
In our simplest geodynamic scenario the Triassic ophiolite components are interpreted as remnants of the Maliac-Meliata Ocean that formed NE of the Pelagonian microcontinent, during the detachment of the latter from Eurasia. During the Middle Jurassic an intra-oceanic subduction zone developed in the Maliac-Meliata Ocean outboard of the Pelagonian-Korab-Durmitor-Drina-Ivanjica margin. Pieces of Triassic Maliac-Meliata ocean floor and seamounts became ripped off the lower plate and accreted in this subduction zone together with very young (0-10 my, supra-subduction) oceanic basalts of the upper plate attributed to the Vardar (backarc) Ocean. When the subduction zone reached the Pelagonian- Korab-Durmitor-Kuci margin, the latter became the lowermost unit of the accretionary wedge. The intraoceanic arc collided with the trench and was overthrust by the young back-arc Vardar crust just before subduction ceased. Further westward thrusting (mostly during Late Cretaceous-Early Tertiary) emplaced this composite ophiolite unit onto the more external Pindos-Cukali zones.
OneGeology-Europe is a project which originated in the global initiative OneGeology. It started in September 2008 and will conclude in October 2010. It is a truly multilateral and multinational project with 29 partners from 20 European countries. The aim of this ECfunded project is to make geological spatial data held by surveys and national geological institutes discoverable and accessible. It will do this through a uniform data model, and create dynamic digital geological map data of Europe. The results of the project will allow researchers, consultants, environmentalists, construction and water industries, planners and local, regional and central governments, to make more informed decisions about the resources and hazards in Europe. It will also provide a means of seeing just what lies beneath your feet!
Major objectives and achievements for OneGeology-Europe include:
• A web-accessible, interoperable, geological spatial dataset for the whole of Europe at 1:1 million scale.
• Accelerating the development and deployment of the emerging international interchange standard language for geological information (GeoSciML).
• Removing barriers and making it easier for a wide range of both public and private sector organizations to use geological data through codes of practice on licensing.
• Creating a common language that helps to acquire geological knowledge and move it closer to end-users for a greater public impact.
• Making substantial progress in the implementation of the INSPIRE European Directive in the geoscience domain.
In addition to the work in the field of informatics, a challenging and important task was the development and agreement of a common geological data specification. The project is delivering a specification for geological spatial data and an interoperable 1:1 million scale dataset for the whole of Europe - an essential platform for the whole project. This foundation includes at its core a vocabulary to describe lithology, age and genesis of the rocks and the tectonic structures and term definitions and their relations. Generic and specific geometric and semantic harmonisation issues were identified. Existing national datasets were then “reworked” to make significant progress towards a harmonised dataset – a crucial step towards INSPIRE goals. The standards, architecture and framework developed by the project can then be “upscaled” to more detailed levels and progressively deployed for higher resolution geological data. The Geological Survey of Slovenia is one of more than 24 data providers in the project. To deliver the Slovenian contribution an existing geological map at a scale of 250000 was edited and simplified to fit the requirements of 1:1 million scale target map. The spatial data were mapped into the common data model and were also party harmonized with neighbouring countries. An additional benefit of Slovenia’s participation in the project will be a new printed geological map of the country in scale 1:1.
The Beysehir Lake, which is one of the largest freshwater lake reservoirs in Turkey, is the most important drinking and irrigation water source for Central Anatolia. The lake has an area of approximately 656 km2 with an average depth of 5 meters. The most important creeks discharging to the Beysehir Lake (Sarısu, Ustunler, Ebulvefa, and Eflatun) and their drainage area form the southeast basin of the lake. The rocks in these basins and their hydrochemical relation with surface and subsurface water will be given briefly in this study.
The Lower-Middle Cambrian Caltepe Formation comprising dolomite, crystallized limestone, and nodular limestone, occurs at the basement and has reservoir rock characteristics. The Upper Cambrian-Lower Ordovician Seydisehir Formation overlies conformably the Caltepe Formation and comprises schist, phillite and shale-bearing limestone and quartzite lenses in places. The Anamasdag Formation, which is the most important reservoir rock in the study area, has widespread outcrops around the lake and rest unconformable on the Seydisehir Formation. It is composed of conglomerate, marl, sandstone, ferric bauxite, dolomite, limestone and is Upper Jurassic-Upper Cretaceous in age. The Hoyran complex comprising serpantinite, pyroxenite, harzburgite, dunite, diabase and chromites emplaced tectonically over the abovementioned units. This unit has outcrops starting from northern part of the Beysehir Lake extending approximately in the NNW- SSE direction up to the Yesildag town located at the south of the lake. Besides, the Eocene Buyukkopru Formation comes unconformable on these units and, begins at the bottom, with the red marl and continues with mudstone – claystone – turbiditic sandstone. The Topraklı Formation is made up of partially consolidated pebble, sand and clay and, covers all the above mentioned units.
The Landsat 5 TM satellite image was used in the interpretation for providing the important hydrological data and individual pollution source in the Beysehir Lake, with its drainage area, which is one of the important water resources in the area. The lineaments and drainage characteristics of the study area have been determined by developing a Digital Terrain Model using filtering methods such as single banded Fast Fourier Transformation and Convolution methods of image enhancement methods. Besides, composites obtained trough hue enhancement and combination in differing ratio of data, in the three visible and three reflected infrared wave lengths occurring of the Thematic Mapper image, give very promising results in differentiating the hydrogeological units and determining pollution spreading in the surface waters. The interpretive linearity and geological maps prepared by supervised and geological map of the area after surface controlling.
Karstification and their size in the limestone which are widespread in the basin and which are mostly forming the reservoir rock were interpreted by means of their chemical analysis results. The permeability of alluvial sediments was determined by means of sieve analysis. The variations in the water level of the lake were interpreted statistically. The chemical analysis results of surface and spring water were evaluated in different diagrams and the possibly of these water as being drinkable and usable were searched.
The project Karpatian Tectonics Slovakia addresses the development of a coherent tectonic model for the Early Miocene in the Vienna Basin and adjacent areas. Studies include 2D/3D seismic interpretation in the Vienna Basin and structural fieldwork in the Outer West Carpathians. Structural data comprises 105 outcrops from the NW-rim of the Pieniny Klippen Belt (PKB) and Outer West Carpathian Flysch units in Northwest Slovakia and Eastern Czech Republic.
Structural data from the Outer West Carpathian Flysch Units (Biele Karpaty-, Magura-, Silesian Unit) depict (N)NW-directed shortening (DF1), which is related to the large scale architecture of the ENE-striking fold-and-thrust-belt. Thrust ages, obtained from the ages of youngest overthrust sediments indicate Eocene to Early Miocene in-sequence thrusting towards the European foreland. Foreland propagating thrusting is also regarded to be responsible for the progressive steepening of thrust units towards the internal parts of the fold-and-thrust-belt, which causes overturning of the innermost flysch units and the PKB.
Crosscutting relationships observed in outcrops give evidence that (N)NW-directed shortening is followed by ENE-striking strike-slip faulting (DF2), reactivating former thrusts of DF1. Strike-slip faults occur at the front of and within the Bystrica and Biele Karpaty Unit close to the PKB. Structures of DF1 and DF2 are further cut or overprinted by (N)NE-striking sinistral strike-slip faults and fold-thrust structures related to (N)NE-directed shortening (DF3). Structural data and geological maps indicate that (N)NE-striking strike-slip faults and NNEdirected out-of-sequence thrusts coincide with bends at the front of the Magura and Bystrica Unit.
Structures from the NW margin of the adjacent PKB prove a complex polyphase deformation history. Multiple folding events, tilted and refolded ramp-flat structures and overturning of strata complicate deciphering individual deformation events and their relative chronology. However, NNW-directed shortening, which postdates large scale overturning of strata, was identified in the region around the Middle Váh Valley. There, the NNW-directed shortening is followed by NNE directed shortening. Deformation styles are comparable with DF1 and DF3 in the flysch units. NNW-directed shortening is interpreted as out of sequence thrusting during deformation DF1. In addition, ENE-striking sinistral strike-slip faults are recorded within the PKB, close to the border to the Biele Karpaty and Bystrica Unit.
The outcrop-derived deformation history is compared to tectonics in the Vienna Basin area, where seismic data provide excellent constraints for deformation ages. In the Vienna Basin, out-of-sequence thrusting coeval with NE-striking sinistral strike-slip faulting occurs in the flysch units and Northern Calcareous Alps during the Early Miocene contemporaneously with in-sequence thrusting in the external Waschberg Unit. Early Miocene NE-striking sinistral strike-slip faults are cut by (N)NE-striking Middle to Late Miocene sinistral strike-slip faults. NE- and (N)NE-striking strike-slip faults mapped in the Vienna Basin are related to the eastward lateral extrusion of the Eastern Alps towards the Pannonian region, whereas (N)NE-striking faults are linked to the pull-apart stage of the Vienna Basin during Middle to Late Miocene times. DF2 and DF3, identified in the Outer West Carpathians are therefore interpreted as to be linked to Miocene extrusion kinematics. ENE-striking strike-slip faulting (DF2) may represent Early Miocene kinematics. NNE-directed out-of-sequence thrusting and (N)NE-striking strike-slip faults (DF3) are interpreted to be linked to the pull-apart stage of the Vienna Basin. Considering several blocks moving towards (N)NE at different velocities during Miocene lateral extrusion, structures of DF3 may depict a transfer of such (N)NE-directed movements to thrusts into the Outer West Carpathians.
Groundwater quality has been recently deteriorating in different alluvial aquifers of Albania due to industrialization expansion, waste disposal, and agriculture activity. A preliminary assessment of vulnerability to groundwater contamination in Erzeni watershed area was undertaken because of enormous mining activities of river bed alluviums, the presence of the largest urban solid waste disposal site of Tirana and intensive agricultural and industrial activities at the plane part of the river course. The major geological and hydrogeological factors that affect and control groundwater contamination were incorporated into the DRASTIC model. Moreover, a Geographical Information System (Arc Gis 9.2 INFO) was used to create a groundwater vulnerability map of Erzeni river basin. Aquifer vulnerability assessment aims at predicting areas, which are more likely than others to become contaminated as a result of human activities at the land surface. As a result of the vulnerability assessment, 20% of the Erzeni basin was classified as being very highly vulnerable, 5% highly vulnerable, 15% vulnerable at moderate to low levels and, finally, around 60% of the basin has very low vulnerability.
Some inherited geophysical evidence in the lithosphere of the SE Carpathians, created by the geodynamic processes related to the W Black Sea opening are subject of the paper.
During the time, various models have been proposed for the Black Sea genesis. They are dominated by the idea of the basin opening within the back-arc extensional environment created behind Pontides by the northward subduction of the Neo-Tethys ocean floor.
Overall, the presence of the oceanic crust in the central part of W and E Black Sea basins is well revealed in the pattern of the geomagnetic anomaly.
But, the hypothesis of the Black Sea opening during a unique geodynamic event is less supported by the residual geomagnetic and gravity anomalies pattern, showing completely different strikes for western and eastern Black Sea. Besides, gravity high, typical for the presence of the oceanic crust correlates with a geomagnetic high (normal magnetization) within W Black Sea, while E Black Sea, the gravity high correlates with a geomagnetic low, advocating for a reverse magnetization of the crust. These aspects advocate for a distinct opening of the W and E Black Sea basins during two time-spans with normal and, respectively, reverse geomagnetic field.
In depth extension of the W Black Sea rifting processes is well revealed by the seismic tomography. Two major issues are well outlined by the geophysical information provided at various levels: the indent representing the lithosphere expelled towards the Carpathians (which is consistent with the two types of the Moesian Platform basement), and the splitting of the Moesian Plate (MoP) into several slivers by reactivation or creation of some deep crustal/lithospheric faults striking north-westward.
Some of the well known regional faults on the Romanian territory (e.g. Sfantu Gheorghe Fault (SGF), Peceneaga-Camena Fault (PCF), Intra-Moesian Fault (IMF)) may be seen as lithospheric boundaries deep to more than 100 km.
After the Black Sea opening ended, it seems that the geodynamic engine in the area became the active rifting within SW Arabian Plate, pushing the plate northward by about 48 mm/year. After accommodating about 15 mm/yr along the North Anatolian Fault, part of the motion is relocated to the Black Sea microplate, pushing the East Carpathians foreland encompassed between PCF and IMF towards NW. Evidence of this push are provided by the Quaternary (Walachian) folds in the bending zone of East Carpathians, and, more recently, by the stress revealed by borehole breakouts studies, or direct geodetic monitoring of the crust deformation along the PCF flanks.
It seems that under this stress, the above-mentioned MoP compartments advance towards the Carpathians kept together by friction. However, from time to time, when tectonic forces overcome the frictional forces the above-mentioned lithospheric slivers may relatively slip each other thus generating earthquakes within their brittle, upper part. This may explain the unusual intracratonic crustal seismicity of the eastern Moesian Platform.
Within the bending zone of East Carpathians, speed excess provided to MoP by the W Black Sea opening created circumstances for the occurrence of an unstable FFT (transform-transform-compression) unstable triple-junction between the three tectonic plates joining the area: MoP, East European Plate (EEP) and the Intra-alpine Microplate (IaP).
Results of a combined inversion of seismic and gravity data are fully consistent with the assumption, by revealing a prismatic triangularly shaped high velocity compartment collapsed into the upper mantle, having vertices parallel to the plate boundaries. Therefore, Vrancea unstable triple-junction (VTJ) might be responsible for the unusual intermediate-depth seismicity within full intra-continental environment. The sinking into the hotter upper mantle of a colder lithospheric compartment generates P-T disequilibrium to which thermo-baric accommodation phenomena (e.g. thermal stress, phase transform processes) may occur as seismic sources.
In depth distribution of the Vrancea intermediate-depth seismicity, with maxima located at the depths where the colder high velocity (seismic) body met the hotter asthenosphere of the surrounding tectonic plates is fully consistent with the assumption.
Geological mapping in the territory of the Slovak Republic has a long tradition. The climax of production of geological maps in the last century was a complete edition of synoptical maps 1:200 000 at the beginning of 60-ies. The centre of gravity in the following period was shifted to systematic geological mapping in the scale 1:25 000. Mapping was organized in particular geomorphologic units – regions. These maps had utilized for compilation of regional maps 1:50 000 which were issued together with book explanations for public using. Hither-to the nearly whole Slovakian territory is covered by regional geological maps in scale 1:50 000. The first regional map 1:50 000 was issued in the 1972 and to the present day number of 47 regional maps from the total of 51 were issued. When compared with other countries it is relatively high per cent covering of the territory. On the basis of the maps 1:50 000 a new “General geological map of the Slovak Republic 1:200 000” has been compiled, which should solve many interregional problems that emerged during the long period of mapping. The map is available in the aggregate form and in the individual sheets as well. The each sheet contents of geological sections, sketches of the tectonic units and the scheme of authors` contributions. The common legend to the General Map has been compiled. The legend to tectonic sketches was compiled in accordance with the principles of the Tectonic map of the Slovak Republic 1: 500 000. The General Map is prepared also in an electronic form, which enables interconnection among single sheets. Common explanatory text to the map was issued in the 2009.
The Slovak Republic is located in the Western Carpathians mountain range. On the new general map actual conception of the geological structure and division of the Western Carpathians is presented. This conception appears from tectonic evolution and succession of the tectonic unit’s origin. Western Carpathians are divided into Outer and Inner as a result from the youngest Neoalpine tectonic processes between the European platform and the Inner Carpathian block. The outer Carpathians are represented by the Flysch belt. A splitting element from the Inner block is the Neoalpine structure of the Klippen belt which contents units from both zones. The inner block is composed of Paleo - alpine tectonic units on which Tertiary sediments and volcanics are deposited.
The Ditrau Alkaline Intrusive Complex (DAIC) is exposed in the southern part of the Crystalline-Mesozoic Zone of the East Carpathians. It is a complex Mesozoic intrusive body, which was incorporated in the Alpine Bucovinian Nappe during the Mid-Cretaceous shortening (the Bucovinian shear plan cut the DAIC at a depth of about 1800 m).
In terms of petrography, DAIC is characterized by diverse rock types, lacking compositional constancy and gradual transitions from one petrographic type to another.
By universal stage (US) plagioclase feldspars from hornblendite, diorite and monzonite cropping out in the left side of the Jolotca valley and along the way Ditrau-Hagota, plagioclase feldspars of nephelinsyenite from the Ditrău valley and plagioclase feldspars from ultramafics cropping out in the right side of the Teasc valley were analyzed. As a result of these analyses we found that a great part of the studied crystals emphasis, zoning, corroding and varying degrees of structural disorder. These plagioclases are generally twin and the twins frequently are complex twin (57.6% of cases) supplemented by parallel and normal twins, equal among themselves in share (21.2% of cases). Contents in anorthite determined by US were verified and detailed by microprobe. They are in the range An 0.09% - An 55% and show numerous frequency peaks. This, in conjunction with succession relations observed microscopically highlighted the existence of several feldspar populations: First plagioclase population that appears in gabbro is represented by an up to An 50% plagioclase. In diorites only exceptionally is present: in zoning structures, or in armoured structures (just in plagioclase core). A second population of plagioclase has a maximum frequency around An 27% - An 30% and appears to be the centre of crystals or around the cores containing over An 40%. It is found in diorite mainly, but in monzodiorite, monzonite or syenite as well. The third plagioclase population has the content around An 20%. It is found mainly in monzonite, syenite, and granite. The fourth population of plagioclase forms a peak at around 14% anorthite. It is not represented in gabbros but since diorite and ending with syenite this is omnipresent. The fifth plagioclase population (albite/oligoclase) appears mainly in the nepheline syenite. Like in all other types of rocks, the nepheline syenite presents a progressive decrease in calcium of the plagioclase feldspars due to the presence of several plagioclase phases. Here, however, the difference in composition between the phases is much smaller. The nepheline syenite oligoclase, rarely exceeds the An 10% - An 12% content but remains at approx. six, seven percent away to the albite which came later. The sixth plagioclases population (we consider the second plagioclase generation) has an albitic composition typically range between An 3% and An 8%. This albite is found in all the rock types from monzodiorite to syenite or nepheline syenite. The albite surrounds all other plagioclase crystals and edits the contact contour of early crystals.
The albite (the second generation of plagioclase) is in a microcline, perthite and sometimes nepheline association while the calcium plagioclase is in a hornblende, sphene and sometimes pyroxene association.
The process of reorganization of first plagioclase feldspars generation is developed to a high temperature level (between the “liquidus” and “solidus” lines of crystallizations diagram) so here an open system evolution process as magma mixing is. The existence of the high plagioclases (plotted on, or near the high temperature curves of the standard stereogram used in US determination) also the existence of the zoning structures, show that the process can not be a metasomatic one.
Ultraviolet (UV) solar radiation plays a very meaningful role in many processes in the atmosphere and biosphere, strongly affecting life on the Earth, and human health in particular. A long term overexposure to UV radiation may cause photoaging, suppression of immune system, skin cancer and cataracts. On the other hand, UV radiation is required for vitamin D3 synthesis and its lack may lead to rickets and other diseases.
Standard measurements of UV radiation are performed with the aid of radiometers situated on the roofs of buildings or masts at the uncovered places, put out directly to the Sun. Data from these measurements are used as a measure of UV radiation influence on human being. Nevertheless, the human body is not a stationary flat surface put out directly to the Sun, so doses of UV radiation obtained from standard measurements do not describe the total UV doses absorbed by human body.
The main objective of this study is to present the results from the comparison of stationary measurements of personal dosimeters Gigahertz-Optik X2000-10 and Solar Light UV-Biometer, and results of measurements of personal UV doses at different human activities. Both meters are designed to measure the erythemal UV radiation.
The comparison of personal dosimeters Gigahertz-Optik X2000-10 and Solar Light UV-Biometer was performed at Legionowo, at different solar zenith angles (SZA) and total ozone (TO). For comparison the reference Solar Light radiometer SL 935, calibrated during international comparison campaigns, was used. The results of dozens measurements at SZA in the range 25-65°and TO from 274 DU to 339 DU, showed a significant dependence of dosimeters correction factor from solar zenith angle.
The measurements of personal UV doses at different human activities have been performed in the Tatra Mountains, during a few excursions at altitude 1000-2000 m above sea level. Measurements were performed simultaneously by two persons and the detectors were fixed on their arms. Personal UV doses were compared with daily doses of UV radiation measured by Solar Light radiometer situated at the IMWM station in Zakopane (855 m a.s.l.). Personal UV dose absorbed by human body during 7-8 hours mountain excursion in clear day is approximately 50% less than daily dose of UV radiation measured by Solar Light radiometer.
Other measurements took place in the eastern part of Poland, during a walk with a child. One detector was fixed to the baby carriage, the other on the arm of the baby-sitter. Detectors fixed to the baby carriage measured the UV dose 50% greater than the other.
Due to the growing water shortage in the summer-dry Eastern Mediterranean, the question of water supply has become an important issue. Since antique times subsurface channels (qanats) have been built, which gather groundwater and take it due to the natural slope to places, where the water is needed. In Greece qanat technology has definitely been used during the Ottoman period. After the liberation and the following Greek-Turkish population exchange the knowledge about the systems has disappeared. There is evidence that many of the subsurface galleries are decayed. On the foothills of the Menikion and Pangeon Mountains active qanate systems have been investigated only recently in order to check their activity, contribution to the local water supply and water quality. The results reveal still working qanate systems, which are endangered by regional land use as well as by systemdestructive building measures.
In an abandoned limestone quarry (Kamenjak) near Arandjelovac (central Serbia), a fossiliferous fissure filling rich in vertebrate remains has been discovered. The quarry Kamenjak is situated on a ridge of the Venčac Mountains, 500 meters to the west of the top. The fissure is approximately 8 meters long with a maximum width of 70 centimeters, trending in north-south direction. It cuts the layers of weakly metamorphized slates and marbles of the Late Cretaceous age (Turonian-Sennonian). The fissure is filled with bone breccia full of bone fragments in reddish matrix of clay, carbonates and limonite.
In this site several samples of bone breccia were collected in 1980 and 1989. Some bones of large and small mammals were extracted from these samples and preliminary described. In this work remains of the following species of rodents have been identified: Spermophilus citelloides (Kormos, 1916), Microtus nivaloides Forsyth Major, 1902, Microtus (Terricola) arvalidens Kretzoi, 1958, Arvicola sp. (cf. cantiana-terrestri), Clethrionomys glareolus (Schreber, 1780), Lagurus sp., Cricetus cricetus Linnaeus, 1758, Mesocricetus newtoni Nehring, 1898, Cricetulus migratorius (Pallas, 1773), Apodemus sylvaticus (Linnaeus, 1758), Apodemus microps (van Kolfschoten, 1985)/A. maastrichtensis (Kratochvil & Rossicky, 1952), Mus cf. musculus Linnaeus, 1758, and Myoxus sackdilligensis (Heller, 1930). Some other small vertebrates (insectivores, lagomorphs, amphibians, reptiles) have also been found in this site. The fossil collections are stored at the Museum of Natural History in Belgrade.
The absolute predominance (about 75% of all rodent remains) of only one species (Microtus nivaloides) suggests relatively harsh conditions during a cold (glacial) period. This species probably preferred open areas, so it can be concluded that such type of environment prevailed in the vicinity of the site. But some forest inhabitants were also present, as well as indicators of more humid conditions (such as shrews).
On the basis of fossil evidence a Middle Pleistocene age has been proposed for this site. The rodent fauna has been compared with the faunas of some neighbouring countries and it has been concluded that it shows most similarity to the Saalian localities from Hungary (Nagyharsanyhegy-6 and Solymar) and Bulgaria (Morovitsa).
This locality is very interesting because it is the first “fissure filling” site of the Pleistocene age in Serbia with small mammal remains. The second important thing is its Middle Pleistocene age – there are many occurrences of Late Pleistocene mammals in Serbia, but remains of Early and Middle Pleistocene age are rare and usually confined to isolated teeth. Many of the mentioned species are reported in Serbia for the first time. So the investigation of this locality will provide us with a better understanding of this period of Pleistocene.
In the preliminary investigations, the age of the fauna from Venčac has been considered as Late Pleistocene, because of morphological similarity between some extant species and their ancestors. An older age can also be rejected, because there are no Mimomys remains, while the genus Arvicola – a characteristic element of Middle and Late Pleistocene rodent faunas – is present. Unfortunately, remains of this genus are very scarce and poorly preserved, so they could not been precisely identified and assigned to a species. The future investigations will hopefully reveal more about this very interesting and rich Middle Pleistocene locality.
We review on a regional-scale the distinct units of the eastern Circum-Rhodope Belt (CRB) in Bulgaria and Greece aiming to provide an up-to-date synthesis and correlation. The eastern CRB consists of Early-Middle Jurassic supra-subduction zone Evros ophiolite, the MORB related Late Jurassic Samorthaki ophiolite and Middle Triassic-Jurassic clastic, pelitic, carbonate and Cretaceous (?) flysch sedimentary successions. The Lower Cretaceous shallow-water Aliki Limestone seals part of these sedimentary successions already metamorphosed in greenschist-facies. Bulk stratigraphy in ascending order comprises a metasedimentary series overlain by a metavolcanic series. The metamorphic grade increases towards the high-grade basement northwards reaching upper greenschist to epidoteamphibolite facies, and decreases to very low-grade (prehnite-pumpellyite facies) and nonmetamorphic stratigraphically upwards in the section. Trace element and REE comparison of the ophiolite basalts and underlying greenschist-facies metavolcanics of same composition reveals similar geochemistry within the distinct units, implying a regional-scale chemical continuity. The allochthonous eastern CRB units show N-directed internal shear deformation and thrust emplacement, obviously along rarely preserved thrust contacts, and record tectonic overprint by Tertiary collision and extensional tectonics in the region. Collectively, the onshore eastern CRB is a region-wide (180 km long along strike ×80 km wide along meridian) tectonic zone including correlative units with regard to their coherent and comparable stratigraphy, tectonics and geochemistry. These units testify for three paleogeographic domains that include Triassic-Jurassic near Rhodope continental margin shallow-water environment, adjacent to this margin Early-Middle Jurassic intra-oceanic arc system responsible for the generation of the supra-subduction zone Evros ophiolite and related to the ophiolite Middle-Late Jurassic trench-slope environment. Another MORB-related paleogeographic domain is indicated by the Samothraki back-arc ophiolite offshore.
The British Museum has a large collection of stone artefacts, including limestone sculptures, from a range of geographical and historical sources. Many of these artefacts are deteriorating and exhibit structural decay, friable or delaminating surfaces, and complications involving soluble salts. The conservation of these artefacts is essential if they are to survive for future generations. Often conservators endeavour to alter a given artefact as little as possible, favouring preventative methods. However, in cases where decay progresses to a serious state where significant portions of an artefact may be lost, more interventive conservation methods may be sought.
The Back to Nature project is a Collaborative Doctoral Award between the University of Oxford and The British Museum. Funded by the AHRC, it is investigating two newly developed techniques; CIPS (Calcite in situ Precipitation System) and Calcium Oxalate treatment, to assess the feasibility of their use within the field of heritage stone conservation. These treatments involve the application of inorganic solutions that react with the stone to produce a consolidant, a material to strengthen and hold an artefact together. These novel techniques mimic natural rock hardening and strengthening processes, and this investigation is situated within a general trend in the conservation field as a whole, to discover treatments that only introduce new materials that are compatible with the original artefact matter. CIPS and Calcium Oxalate treatment are being analysed in comparison with the group of more traditional organic consolidants known as Organo Silanes.
This poster presents the pilot study of the Back to Nature project. Designed with the broad aim of trialling the conservation treatments and to highlight any possible issues with the experimental design, there are two specific objectives of the pilot study. The first is to examine the difference in a select set of measurements between fresh and weathered stone samples. This will examine the importance of the source of sample material, and the issue of whether fresh stone samples can really provide an accurate substitution for artefacts that may have undergone thousand of years of weathering. The second objective is to determine the minimum number of replicates required for an adequate and meaningful comparison of consolidation treatments. The results of these two objectives will provide a basis for the methodology adopted for the Back to Nature research, enhancing the value and reliability of data obtained from future experiment essential to the project, and the results may have wider reaching consequences for the interpretation of data from other stone conservation investigations.
With this abstract we try to schematically reconstruct a portion of the long story of the southern Dinaric-Hellenic, basing our effort on the complex tectono-stratigraphic evolution of the Dinaric ophiolites. First of all, we propose a new classification of the ophiolites cropping out in Albania and Greece that includes seven different types of occurrences, which correspond to different tectonic “units”. From bottom upwards they are: 1- the Sub-ophiolitic Mélange (SOM); 2 - the Triassic Ophiolites (TOP); 3 - the Metamorphic Soles (MES); 4 - the Jurassic Ophiolites with MOR and SSZ magmatic sequences (JOa); 5 - the Jurassic Ophiolites with only SSZ magmatic sequences (JOb); 6 - the Supra-ophiolitic Mélange (UOM); 7 - the Jurassic Ophiolites with BABB magmatic sequences (JOc). The features of these ophiolites (stratigraphy, geochemistry, tectonic setting and age), the same all over the southern portion of the Dinarids from Albania to eastern Greece, strongly suggest the existence of a single ocean located east of the Adria/Pelagonian continental margin: the Vardar Ocean. This ocean basin developed during the Middle Triassic and was subsequently affected since Early Jurassic by an east-dipping intraoceanic subduction leading to the formation of SSZ magmatism. This subduction was thus responsible of the birth of fore- and back-arc oceanic basins separated by a volcanic arc during Middle to Late Jurassic. This event was followed by the obduction during which a section of oceanic lithosphere thrust westwards onto the Adria margin at the Jurassic-Cretaceous boundary, and the ocean was completely effaced. From this period to the Eocene the westward movement of the Ophiolites on the Adria continental margin, for more than 200 kilometres, till the Pindos took place
We also believe that the model of geodynamic evolution presented herein can be extended to the all Dinaric-Hellenic orogenic belt.
In the Bulgarian Central Rhodopes, the lower part of the metamorphic pile is dominated by migmatitic orthogneisses having recorded fluid-assisted partial melting at 650-700ºC / 6-8 kbar. Several zircon and monazite U-Pb ages around 36-38 Ma have been reported, interpreted as dating the crystallization of melts. In the area of Chepelare, this pile is exposed as a ~5 km-thick north-dipping monocline. Structures document top-to-SW shearing developed during and subsequent to anatexis. In the middle part of the section, the ~1 km thick Chepelare Shear Zone (CSZ) reflects late Eocene syn-metamorphic thrusting and exposes a variegated rock assemblage of highly sheared migmatitic gneisses hosting discontinuous layers of marbles, garnet-kyanite gneisses, metabasites, and ultramafics.
In order to constrain the P-T-time evolution of this variegated rock assemblage, we present new petrological and geochronological data obtained from garnet-kyanite gneisses. The samples represent melt-depleted residual granulite composed of zoned garnet and kyanite porphyroblasts of centimeter size in a low-portion matrix of K-feldspar, quartz and biotite. The latter forms retrograde rims around garnet, and together with kyanite, defines a rough foliation. In some samples fibrolite partially replaces synfolial biotite. The accessory mineral assemblage comprises monazite (up to 400 μm), apatite, zircon, rutile, ilmenite, staurolite, and graphite, found in the matrix, and as single or polyphase solid inclusions in garnet and kyanite porphyroblasts. Polyphase inclusions mark core-rim boundary in zoned kyanite and consist of K-feldspar, quartz, monazite, apatite, rutile, graphite, ± zircon, ± biotite. Planar faces of mineral grains suggest crystallisation of trapped melt. Graphite nucleation indicates participation of carbon-saturated fluids.
U-Th-Pb analyses on monazite were performed by means of LA–ICPMS in thin sections. The results yield two age groups related to the textural position of the monazite grain (included in a garnet or kyanite porphyroblast vs. in the matrix). Mesozoic ages, between 137 and 142 Ma, are most common. They were obtained in all monazite included in garnet as well as in polyphase inclusions in kyanite. P-T estimates based on the metamorphic record preserved in garnet and kyanite suggest granulite facies anhydrous melting, or low aH2O fluid participation, at > 800ºC / > 1.2 GPa, that produced peritectic garnet (and probably kyanite) together with a K-rich melt. In the same samples, Cenozoic ages between 38 and 42 Ma were obtained in the outer rim of monazite grains located in the matrix. These monazites also preserve Mesozoic ages in the grain core. The Cenozoic ages relate to the tectonometamorphic event that led to widespread fluid-assisted partial melting in adjacent orthogneisses. During this event, because they represent a melt-depleted residue with respect to a previous higher grade melting event, the garnet-kyanite gneisses remained unfertile and preserved good petrological and geochronological record of the older event. Nevertheless, they also recorded the Cenozoic event in at least two ways, namely the growth of fibrolite at the expense of biotite, and the partial recrystallization of monazite grains located outside large porphyroblasts.
Finally, an interesting result of this study is the first documentation, in the Bulgarian Central Rhodopes, of a Late Jurassic-Early Cretaceous high-grade metamorphic event that is also known from the Greek part of the Rhodopes Mountains (e.g., in the hanging wall of the Nestos Shear Zone).
The Moesian platform occupies a large area in Bulgaria and Romania. A lithostratigraphic division of the cross-section of the Triassic system is performed for both countries. The applied methodology in defining the lithostratigraphic units is based on the “International stratigraphic Guide” by Hedberg. Although the present work aims to unify positions and technical usage of the lithostratigraphic units the latter are rather different in Bulgaria and Romania, which makes difficult the cross correlation.
The Bulgarian part of the Moesian platform is examined according “Regional lithostratigraphic scheme of the Triassic sediments on borehole sections in North Bulgaria”.
The lithostratigraphic division for the Romanian part is based on publications. The following lithostratigraphic units are determined in the Moesian platform:
In the Lower red colour complex: Bulgaria - Petrohan Group and Red colour sandstone unit, Stejerovo Fm., Alexandrovo Fm. and Dobrudja Fm.; Romania - Vedea-Jiu Group (Carboniferous-Permian-Scythian), Rosiori Fm. (Permian-Scythian) and horizons Bradesti and Viisoara;
In the Carbonate complex: Bulgaria – Iskar Group, Doirentsi Fm., Mitrovtsi Fm., Russinovdel Fm., Preslav Fm. and Tulenovo Fm.; Romania - Alexandria Fm. (Permian-Scythian-Anisian), Putinei evaporites.
In the Upper variegated colour complex: Bulgaria - Moesian Group, Kozlodui Fm., Komshtitsa Fm., Gorni Dabnik Fm., Tuchenitsa Fm., Dulovo Fm., Kaliakra Fm. and Shabla Fm.; Romania - Oltet Group (Triassic-Lias-Dogger), Segarcea Fm., horizons Curmatura, Beiu and Teascu, Motoci complex.
The present correlation determines three type of units: A) Analogous units (subjective synonyms); B) Units defined on Bulgarian territory and probably present also in Romania; C) Units located only in Bulgarian and respectively in Romanian part of the Moesian platform.
The detailed research and well investigations demonstrate the following results:
A) Analogous units (subjective synonyms):
In the Lower red colour complex there are Red colour sandstone unit (Bulgaria) – Bradesti horizon (Romania); Stejerovo Fm. (Bulgaria) – Viisoara hor. (Romania); Petrohan Group (Bulgaria) – Triassic part of the Rosiori Fm. (Romania, Permian-Triassic) and Vedea- Jiu Group (Romania, Carboniferous-Permian-Scythian).
In the Carbonate complex have been established Doirentsi Fm. (Bulgaria) – Anisian parts of the Alexandria Fm. (Romania, Permian-Scythian-Anisian).
In the Upper variegated colour complex there are Komshtitsa Fm. (Bulgaria) – Curmatura hor. (Romania); Gorni Dabnik Fm. (Bulgaria) – Beiu hor. (Romania); Dulovo Fm.(Bulgaria) – Teascu hor. (Romania); Moesian Group (Bulgaria) - Segarcea Fm. (Romania) and Triassic part of the Oltet Group (Romania, Triassic-Lias-Dogger).
B) Units defined in Bulgaria and probably developed also in Romania:
In the Lower red colour complex there is Alexandrovo Fm.
In the Carbonate complex there are Mitrovtsi Fm., Russinovdel Fm., Preslav Fm. and Iskar Group.
In the Upper variegated colour complex there is Kozlodui Fm.
C) Units characteristic only of Bulgaria, respectively only of Romania:
In the Lower red colour complex have been established Dobrudja Fm. (Bulgaria), Scythian carbonates (Romania, part of the Alexandria Fm.).
In the Carbonate complex there are distinguished Tulenovo Fm. (Bulgaria), evaporites from Putinei (Romania).
In the Upper variegated colour complex there are Tuchenitsa Fm. (Bulgaria), Kaliakra Fm. (Bulgaria), Shabla Fm. (Bulgaria), Motoci complex (Romania, sedimentaryvolcanogenic).
A laboratory batch study has been performed to investigate the adsorption characteristics of lead (Pb2+) metal ions onto natural bentonite samples (B1, B2, B3) with different cation exchange capacity (CEC) values. Bentonite samples come from Milos island, Greece and were supplied by S&B Industrial Minerals S.A. Bentonites consist mainly of Ca-montmorillonite (>85%) with minor and different amounts of kaolinite, calcite and quartz. The CEC values of B1, B2 and B3 were 86.5 meq/100g, 95.7 meq/100g and 67 meq/100g, respectively. The specific surface area of B1, B2 and B3 was measured as 87.3 m2/g, 66.6 m2/g, and 80.1 m2/g, respectively. Equilibrium and kinetic experiments were performed. The effect of various physicochemical factors that influence adsorption, such as solution pH (2-6), amount of adsorbent (1-10 g/L), initial metal ion concentration (5-150mg/L), and contact time (20-360 min) were studied. The measured adsorption capacity was appreciably high for most experimental conditions. It has been found that the amount of adsorption of lead metal ion increases with initial metal ion concentration, contact time, solution pH but decreases with the amount of adsorbent. The adsorption process was strongly dependent on the pH of the medium with enhanced adsorption as the pH turns from acidic to alkaline side till precipitation sets in. The amount of Pb2+ adsorbed per unit mass (qe) of the adsorbent decreased with an increase in the amount of the clay adsorbent. This may be attributed to two reasons: (i) a large adsorbent amount effectively reduces the unsaturation of the adsorption sites and correspondingly, the number of such sites per unit mass are reduced resulting in comparatively less adsorption at higher adsorbent amount, and (ii) higher adsorbent amount creates particle aggregation, resulting in a decrease in the total surface area and an increase in diffusional path length both of which contribute to decrease in amount adsorbed per unit mass. The removal rate of bentonite increased with an increase in the initial metal ion concentration. Both Langmuir and Freundlich isotherm models fit well (R2>0.93) the adsorption process. By using the Langmuir isotherm, the maximum adsorption capacities for B1, B2 and B3 were found as 85.47 mg/g, 73.42 mg/g and 48.66 mg/g, respectively. In order to investigate the mechanism of adsorption, particularly potential rate-controlling step, the Lagergren pseudo-first-order kinetic model, the pseudo-second-order kinetic model and the intra-particle diffusion model were used to test the dynamic experimental data. Kinetic analyses not only allow the estimation of sorption rates, but also lead to suitable rate expressions characteristic of possible reaction mechanisms. The calculated kinetic parameters are of a great practical value for technological applications, since kinetic modeling successfully replaces time- and material-consuming experiments, necessary for process equipment design. Kinetic experiments clearly indicated that adsorption of lead metal ion (Pb2+) on bentonite was a two steps process: a very rapid adsorption of lead metal ion to the external surface was followed by possible slow decreasing intraparticle diffusion in the interior of the adsorbent which has also been confirmed by intraparticle diffusion model. Overall the kinetic studies showed that the lead adsorption process followed pseudo-secondorder kinetics.
The objective of this study was to characterize urban road dust particles and to study their possible health effects. Road re-suspended dust has been recognized as one of the major contributors to TSP elevating concentrations in Thessaloniki. Eight samples of road dust were collected from the accumulated matter at the edges of major roads in the historic centre of the city of Thessaloniki. The predominant size fraction, according to mass, was 125–500μm, while the mass fraction of the suspendable dust particles (20-63μm and <20μm) was the lowest. Special emphasis was given to the mineralogical characteristics of the urban deposits. Road dusts were mainly composed of quartz, calcite, while plagioclase, dolomite, Kfeldspars, amphiboles, micas and chlorite were contained in minor amounts. Amorphous phase was also determined mainly in the finer fractions (20-63μm and <20μm). Scanning electron microscopy shows that dust particles consist of subhedral to anhedral crystalline grains, near-spherical and irregular agglomerates as well as few organic materials. EDS analyses reveal that the composition of dust particles is basically Ca-rich, Fe-rich and silicates.
The primary aim of the research is to investigate the accumulation and distribution of organic material [OM] in saline shallow lacustrine sediments. This study focuses on the OM parameters of sediments at two areas with different hydrology, land use, and vegetation cover. The study area is located at the Fehér Lake, Szeged (Hungary). The studied salt-affected lake system has been under intensive fish breeding from 1970. Sampling was made during the spring of 2007. In case of the profiles a 4 m deep 10 cm diameter sediment core was extracted. The OM data were measured with Rock-Eval pyrolysis, and the proportion of different OM groups was determined by the mathematical deconvolution of Rock-Eval pyrograms. It is showed that there are significant differences in OM distribution and characteristics if the different study sites are compared. In case of both profiles similar changes can be detected in the origin, quantitative and qualitative parameters of OM at depths of 15, 30, and 65-70 cm, which proves that the two sites belonged to the same depositional system, and similar changes affected them during sediment formation. Although both profiles have the same depositional environment, significant difference can be seen between the profiles. The profile 1 used to be located in coastal natural territory till 1970 and the profile 2 represents a constant water-irrigated fields. The fluctuation of F1+F2 and F3 values in Profile 1 suggests that the OM content of the marginal territory (both in its natural and present state) is determined by the alternation of dry and wet periods, sometimes with a high algae production in slack waters. Based on the quality parameters of OM, dry and wet accumulation periods can be separated, and signs of human influence can also be identified.
Kotel’nyi Island is located in the Arctic Ocean near to the prolongation of Southern Anyi ophiolite suture zone which is supposed to be remnant of southern Anyi Paleo-ocean located between Eurasian and North American plates. Therefore the information on Early Mesozoic faunas of this area and their paleobiogeographic affinities represent high interest for paleogeography and paleotectonics. Triassic of Kotel’nui Island is represented by all three series that are well characterized by ammonites, nautiloids, coleoids, bivalves and radiolarians. Section is characterized by predominance of soft clays. Radiolaria are present in the Middle and Upper Triassic, from Upper Anisian to Middle Norian.
The Middle Triassic is represented by Anisian black clays with interlayers of bituminous shales, clayey limestones and phosphatic concretions with total thickness 30 - 140 meters. Ladinian is composed of similar clays with thickness 6 - 15 meters. Radiolaria were found in the Upper Anisian together with ammonites Indigirophyllites popowi Konstantinov. They are represented by Glomeropyle clavatum Bragin, sp. nov., G. boreale Bragin and others (11 species). Next radiolarian assemblage was found in the Upper Ladinian (with bivalvs Daonella sp. ex gr. D. frami Kittl.): Muelleritortis firma (Gorican), M. kotelnyensis Bragin, sp. nov., and others (10 species). Upper Triassic is represented by Carnian clays with siderite and phosphatic concretions (100 m) and Norian clays with siderite and phosphatic concretions (up to 500 m). Radiolaria are present in the Lower Carnian (with ammonoids
Discophyllites taimyrensis Popov): Pentactinocarpus colum Bragin, sp. nov., Glomeropyle cuneum Bragin, sp. nov., and others (12 species); Upper Carnian (with ammonoids Yakutosirenites yakutensis (Kiparisova): Pseudostylosphaera glabella Bragin, sp. nov., P. gracilis Kozur et Mock, and others (34 species); and in the Lower Norian (with ammonoids Striatosirenites kinasovi Bytschkov): Pseudostylosphaera glabella Bragin, sp. nov., P. gelida Bragin, sp. nov., and others (10 species). Each radiolarian assemblage includes several forms know from low-latitude regions as Mediterranean and Japan. These taxa constitute from 25 to 40 % of all species present in assemblage/
These results allow making several conclusions:
1) The sections include several radiolarian assemblages ranging from late Anisian to the early Norian. Taxonomic diversity of the assemblages increases at the stratigraphic levels rich in phosphorites and bituminous shales, which probably correspond to transgression episodes and well correlate with intervals of abundance of cephalopods.
2) Triassic radiolarian assemblages from Kotel’nyi Island significantly differ from the coeval radiolarians of Pacific and Mediterranean. They are characterized by domination of genus Glomeropyle Aita et Bragin which is present only in Northern Siberia and in the New Zealand and displays bipolar distribution pattern. Triassic radiolarian assemblages of these regions display clear affinity. Radiolarians can serve as paleoclimatic indicators for the Triassic.
3) The Middle Triassic radiolarian assemblages from Northern Siberia and regions of Mediterranean and Pacific include a number of common species (25-40 %). Using them, we can correlate Triassic deposits. This approach is helpful for solving the basic problem of correlation between Triassic deposits accumulated in the high- and low-latitude zones.
4) The presence of low-latitude species in radiolarian assemblages is well correlative with constant presence of low-latitude taxa among cephalopods. Their assemblages include several species known from Mediterranean and North America. These facts can be explained as results of marginal position of Kotel’nyi Island in the Boreal Realm and well connections between basins. We can interpret the appearance of warm-water taxa by the influence of warm current coming from Pacific via suspected North Anyi Paleo-ocean.
Sedimentary strata related with ophiolites commonly represent high interest for tectonostratigraphic reconstructions. Upper Cretaceous Perapedhi Formation represents lowermost part of sedimentary cover of Troodos Ophiolite Complex, and consists of umbers (sediments enriched by iron and manganese) and cherts with total thickness ranging from few meters up to nearly 50 m. These sediments are characterized only by radiolarians that still need detailed study.
Best section of Perapedhi Formation is known in the former Mangaleni quarry, Limassol District. Three lithological units can be distinguished in this section: 1 – dark-brown massive umbers (2-20 m), 2 – intercalation of brown umbers and brown radiolarian cherts (6- 10 m), 3 – pink ribbon cherts (up to 6 m). All units are characterized by abundant wellpreserved radiolarian assemblages. According to stratigraphic distribution of radiolarian taxa the following radiolarian zones and subzones can be distinguished in this section:
1. Alievium superbum Zone, Turonian, Theocoronium subtriquetrus Subzone. First occurrences (FO) of Pseudodictyomitra sp. A and Theocampe cypraea Bragina (middle part of unit 1).
2-3. Alievium praegallowayi Zone, Coniacian, subdivided into: 2. Multastrum regale Subzone, FO of Archaeospongoprunum bipartitum Pessagno, Annikaella omanensis De Wever (middle part of unit 1 – lower part of unit 2); 3. Microsciadiocapsa quasisutterensis Subzone, FO of: Lipmanium (?) ovalum Bragina (lower part of unit 2).
4-7. Alievium gallowayi Zone, Santonian – Lowermost Campanian, subdivided to: 4. Quinquecapsularia sp. A Subzone, FO of Theocampe urna (Foreman) (lower – middle part of unit 2); 5. Dorypyle sp. A Subzone, FO of Acanthocircus sp. A, Dictyodedalus sp. A (middle – upper part of unit 2); 6. Multastrum mangaleniense Subzone, FO of Amphipyndax sp. ex gr. A. pseudoconulus (Pessagno) (lower part of unit 3); 7. Bisphaerocephalina (?) amazon Subzone, FO of Dorypyle sp. B, Neosciadiocapsa urquharti Bragina, Theocampe salillum Foreman (middle part of unit 3).
8. Crucella espartoensis Zone. FO of Dictyomitra koslovae Foreman subsp. B, Heliocryptocapsa sp. B (upper part of unit 3). Therefore the total stratigraphic range of this section is Turonian – Lowermost Campanian
Another section of Perapedhi Formation was studied near Perapedhi Village, Central Cyprus. It is represented by umbers with recrystallized chert bodies and rare layers of pink padiolarian cherts with total thickness 10 m. These strata yield radiolarian assemblage of Subzone 6 only (Multastrum mangaleniense).
Therefore, the deposition of metalliferous sediments of Perapedhi Formation was diachronous. In the Mangaleni Section it starts in the Turonian, but in the Perapedhi Section it was considerably later (Santonian). This phenomenon can be interpreted as result of deposition of Perapedhi Formation in isolated small depressions of Troodos Ophiolite Complex that was completely formed in Turonian.
We define geomorphologic landscape (GL) as the complex of geomorphologic, tectonic, and landscape-climatic characteristics incident to a certain territory. Such complex includes absolute height, amplitude of neotectonic movements, their gradients, the depth of erosion dissection ant its density, intensity of landslide, karst, thermokarst and glacial processes, the amount of woodlands and the degree of peat formation, precipitation, runoff, and frost-free period. The territory analyzed includes the East-European Plain, the Ural Mountains, and the Western Siberia. The 20’x30’ spatial cells, described by the above mentioned 15 parameters, were clustered by k-means method with different k values. Euclidean distance was used. The results of clustering are represented as maps, where spatial distribution of different clusters, or GL, can be seen. Each GL is characterized by the set of parameter means, which determine the shape (the type) of a given GL. According to F-ratio the geomorphic parameters play the significant if not the main role in clustering. The set of cluster solutions with k=2, 5, 9, and 17 are represented.
The two plains have some common GLs only at rough division with small k values; at k=2 there are two variants of division: first – mountainous (The Urals) and plain GLs, second – GLs of the accumulative plain (the Western Siberia) and of the erosion-denudation plain. At k=5 the northernmost and the southernmost parts of the plains have common GLs: tundra GL of permafrost-erosion dissection and GL of semiarid plains with extremely low erosion and denudation correspondingly. GL of boggy lowlands with low neotectonic intensity and low erosion occupies the central part of the West Siberia while GL of neotectonic highlands with intense erosion dissection and complex of denudation processes occupies the most part of the East-European Plain. More detailed divisions (with k=9, 17 and more) show clear difference between the two plains, and at k=20 they have no common GLs. The GLs of the Western Siberia have less dispersion of parameters, i.e. they are more homogeneous, and their boundaries show stronger dependence on the latitudinal zonality than those of the East-European Plain. The latter reveals more diversity of GLs than the Western Siberia. The Urals having the GLs of the “mountain” type don’t form the single area: the most part of the Middle Ural falls into the GLs of the East-European Plain types at any k value.
The tree clustering of the GLs themselves (Euclidean distances, Ward method) demonstrates their hierarchical structure, which is in good agreement with the results of kmeans method. The spatial GL’s boundaries are sufficiently stable to the changes of k values and to the variation of the set of parameters. The approach described can be used also as a method of typological regionalization in other geographic regions.
In alkali basaltic rocks scarcely appear accessory minerals such as zircon and corundum. The origin of these mostly gem stone like mega-crystals is unknown and controversial. However, if zircon crystals present they are important tools to clarify petrogenetic questions of the host melts. Host magmas of the zircon mega-crystals are normally SiO2 under saturated such as basanites and nephelinites.
In several localities we could observe some zircon mega-crystals and in a quarry in Saxony (eastern Germany) we collected 36 crystals up to 15 mm in size in situ from the basanitic rock. Zircons occur in agglutinates of lower crater facies of a scoria cone. The related lava flows are almost free of zircons and their Zr contents reaches up to 900 ppm. There is a good correlation between Ar/Ar data of the basanites (30 to 31 Ma) and the zircon U/Pb data which show ages about 30.5 Ma.
A further known locality of zircon mega-crystals is the so called Seufzergründel placer in Elbsandsteingebirge / Saxon Switzerland (eastern Germany). There are observed zircon mega-crystals up to 9 mm in size. Their host rock is a lapilli bearing volcanic breccia, implying here a polyphase explosive volcanism. The age data of zircons have various values; while the Pb/Pb crystallization-ages range by 54±6 Ma the U/Pb dating gets about 35 Ma.
Furthermore zircon mega-crystals were sampled from placers and residual soil of basanitic and nephelinitic as well as phonolitic rocks from different localities via heavy mineral separation techniques. The crystals show an intensive magmatic corrosion in alkalibasaltic rocks (including nephelinites), while zircons out of phonolites are mostly euhedral.
Thus the zircon mega-crystals were carried by alkali basaltic magmas but were not in equilibrium with these melts. Basaltic host rocks of the mega-crystals are developed of primitive mantle melts, implying a short residence time for zircons in the melt. The solution rates of zircon in such melts are possibly high which could be seen in the intense magmatic corrosion. Therefore zircon mega-crystals occur mostly in pyroclastic rocks and are scarce or absent in massive lava flows. The latter have a much longer cooling time.
Another possibility for enrichment of mega-crystals in pyroclastic rocks should be that the ascending bubbles in the vent carry away the solid parts, like xenocrystals or phenocrystals of the magma column. This could be the reason for lacking of in situ proofs of zircons in massive basalts.
The age data of the zircons in relation to that of the host rocks imply a cogenetic development of both.
The Pieniny Klippen Belt (PKB) is a narrow (merely several km), but lengthy (up to 600 km) zone dominated by Late Oligocene – Miocene wrench tectonics. It separates the Cenozoic accretionary complex of the External Western Carpathians from the Cretaceous nappe system of the Central Western Carpathians. Our investigation was focused on the tectonic structure and evolution of the Vršatec klippen area in the western Púchov sector of the PKB. The studied area includes the Oravic (Czorsztyn, Kysuca, Orava and Transitional Units) and the “non-Oravic” tectonic units (Klape and Drietoma Units). Detailed geological mapping and systematic field structural research of meso-scale deformational structures revealed the record of multistage tectonic evolution during Senonian-Pliocene times. The oldest recognized stage resulted in formation of the Mesoalpine fold-nappe system of the PKB due to subduction and closure of the Vahic Ocean during the Senonian – Early Eocene times. This compressive stage was accompanied by thrusting of the presently most external Kysuca Unit over the Czorsztyn and transitional units and by formation of macroscopic folds with the NNE-SSW to NE-SW trending fold axes. The main compression was oriented perpendicularly to the strike of the PKB recently trending in the SW-NE direction. The thrusting and folding were followed by several brittle deformation stages. The oldest stages (E-W to NW-SE oriented maximum compression) produced the NE-SW trending dextral positive flower structure along the western boundary of the PKB and resulted in the final morphostructural character of klippen with long axes oriented in the NE-SW direction. The dextral transpression was a result of the continuing shortening and relative counterclockwise rotation of the ALCAPA block in the Late Oligocene – Early Miocene. The younger N-S oriented compression (Early – Middle Miocene) produced mainly sinistral faults roughly parallel to the strike of the belt in the sinistral transpression regime. The apparent shift of the main compression to the N-S direction was an effect of a rigid counterclockwise rotation of the ALCAPA block during the Early Miocene. Mostly strike-slip and normal faults were formed during the next two tectonic events (Middle to Late Miocene) as a product of the transtensive tectonic regime with NNE-SSW to NE-SW trending compression. Active clockwise rotation of the main compressional stress axis from N-S to NE-SW direction, and inversion from the older transpression to the younger sinistral transtension resulted from NEward translation of the ALCAPA block. The NE-SW trending normal faults were generated by the NW-SE extension during the final deformational phase under the extensional tectonic regime (Pontian-Pliocene).
The Lower Cretaceous deposits from Bihor-Pădurea Craiului unit follow a sedimentary gap due to the uplift of the region at the end of the Late Jurassic, when bauxitic rocks were formed. The succession consists of the following lithostratigraphic units: (1) Blid Formation, comprising two members: (1a) Dobreşti Member (Valanginian-Hauterivian) known in the old literature as “Limestone with characeans and gastropods”), and (1b) Coposeni Member (Barremian), the old “Lower Pachyodont limestone”; (2) Ecleja Formation, consisting mainly of marls, but containing also two lithologically different members: (2a) Gugu Breccia Member (Upper Barremian), and (2b) Valea Bobdei Limestone Member (Lower Bedoulian), corresponding partly to the old “Middle Pachyodont limestone”; (3) Valea Măgurii Limestone Formation (Upper Bedoulian), also corresponding partly to the old “Middle Pachiodont limestone”, and (4) Vârciorog Formation (mainly marls and sandstones, with limestone intercalations) (Gargasian-Albian) that correspond to the old “Formation of glauconitic sandstones and Upper Pachyodont limestone”. Of these lithostratigraphic units Dobreşti Member and Ecleja Marls have been often a subject of controversy. The age of Dobreşti Member proved to be Valanginian-Hauterivian. Regarding the Ecleja Marls, recent researches revealed that the succession of the startotype is younger as considered before (Late Aptian-Albian, instead of Late Barremian-Early Aptian). Other recent researches have shown the development of a large pile of Upper Aptian-Albian platform limestones, equivalent of limestone intercalations within the Vârciorog Formation. These new data change our understanding of the Bihor-Pădurea Craiului basin evolution during the Aptian-Albian time interval. At the biginning of Aptian, a deeper basin was formed. On local highs within the basin isolated carbonate platforms developed (Valea Bobdei, Valea Magurii, and Subpiatra Limestones). Material from these platforms can be found as debris flows (allodapic limestones) intercalated in the terrigenous succession of the basin. Within the Villany Hills (Hungary) the Nagyharsány Limestone formed also on the Upper Jurassic Szársomlyó Limestone Fm revealing bauxite lenses (Harsányhegy Bauxite Fm) at its base. The age of the Nagyharsany Limestone wich consists of four lithologic (calcareaous) members is considered as Valanginian-Early Albian. It is covered by the Bisse Marls of Late Albian-Cenomanian age. No other marl intercalations were reported from the Nagyharsany Limestone.
The Bisse Marl is replaced at a marked contact by flysch type succession of the Bóly Sandstone Formation in the Late Albian. Based mainly on micropaleontological association the lower part of the Villány succession could be compared with the Dobreşti and Coposeni members of the Blid Formation, while its middle and upper parts of the Nagyharsány Limestone could be correlated with Valea Bobdei-Valea Măgurii, and Subpiatră Limestones, respectively. The Vârciorog Fm is equivalent to the Bisse and Bóly Formations.
Acknowlegdments: The study was partly financed by CNCSIS (grant ID_95, Ioan Cociuba), and by Alexander von Humboldt Fountation (Ioan I. Bucur).
The diagenetic history of the Upper Eocene tuffs in the West Thrace Basin is based on petrological analysis of samples from six boreholes. Diagenesis in the tuffs principally involves the progressive development of various types of cements in the following order: quartz overgrowth, zeolite authigenesis, chlorite and illite authigenesis. After the formation of the cementation phases, there was a dissolution phase creating secondary porosity via the dissolution of volcanic class and feldspars, accompanied by generation of analcime and a late mordenite cementing phase. The tuffs also have been affected by the following diagenetic processes; fracturing and calcite, quartz, and zeolite cementation.
Tuffs in the West Thrace Basin may contain significant amounts of secondary porosity owing to unstable grain and volcanic glass dissolution caused by relatively rapid rates of pore-fluid flow. Also tectonic stress appears to have controlled development of secondary porosity formation in the West Thrace basin which in turn might have been responsible for high porosity of the deep reservoirs. At depths greater than 2000 m, the porosity increases with depth due to secondary solution activities and fracturing in the West Thrace basin. Secondary Porosity is very important for hydrocarbon explorations in the Upper Eocene tuffs in the West Thrace basin. The dominant porosity type produced by dissolution processes (intragranular, intergranular). Fracture porosity also significantly increases reservoir quality. Authigenic clays may affect reservoir quality depending on type of clay and its distribution. However, dissolution and fracturing are generally a more effective diagenetic process than cementation in the tuffs of West Thrace basin.
The aim of the study is to identify specifically temporal and spatial patterns of the intermediate seismic activity in Vrancea seismic zone using new approaches. We have investigated the influence of the principal lunar semidiurnal tidal component M2 on intermediate seismic activity in Vrancea (Romania) sub-crustal region from 1934 to 2009 with a special regard for the time series of events from 1980 to 2009. The constituent is assigned by HiCum stacking method according to the earthquake occurrence. “Schuster” and “Permutation” independent tests are applied to distributions found by stacking. Null hypothesis between seismic activities and selected tidal periodicities is rejected when the statistical p-values obtained by the two tests are less than 5% level of confidence in term of statistics. The stacking function is applied to time series of events belonging to windows shifted in time and space, respectively, to evaluate the variability of correlations in both cases. In the case of 3D shifting domain, a specific algorithm, called “statistical tidal tomography”, is described. The results reveal important issues: a) There is a specific temporal footprint of the p-values around the larger earthquakes; b) A Fast Fourier Transform on the n-order polynomial least squares fit (LSF) of the p values variations emphasizes a long-term period about 17 – 18 years; c) Following the 3-D distribution of p<5% values in different sliding time windows we observe a certain pattern confirmed by the CN algorithm for the earthquake prediction and the future strong Vrancea events monitoring; d) the statistical tidal tomography of M2 component has similar patterns with the analysis of seismicity patterns introduced by others for the Vrancea seismic region.
The Rhodopeian Orogen developed since Late Cretaceous-Lower Eocene during accretionary processes following the closure of the Vardar ocean basin. We concentrate on Paleogene clastic sediments of the Rhodope area, developed synchronous to the post – Cretaceous collisional collapse and the subsequent Tertiary extensional phase. Throughout a multidisciplinary approach, including sedimentary petrology, sandstone geochemistry and compositional data analysis, we argue to reconstruct the unroofing history of the Rhodopian orogen and the abrupt onset of the volcanic activity between Late Eocene and Oligocene across the eastern and southern Rhodopian region. A total of 127 sandstone samples have been analysed. Sandstone detrital modes include three distinctive petrofacies, a quartzolithic, quartzofeldspathic and volcaniclastic. The major contributions are from the metamorphic basement units, represented mostly by low-medium grade lithic fragments for the quartzolithic petrofacies and high grade metamorphic rock fragments for the quartzofeldspathic petrofacies. Volcaniclastic sandstones recorded different composition betweeen eastern Rhodopes and southern Rhodopes samples. Detrital mode evolution testifies contributions from three key source areas corresponding with the two main crystalline tectonic units of the Rhodope Massif, Variegated Complex and Gneiss-Migmatite Complex and from the Circum-Rhodope Belt. The volcaniclastic petrofacies is interbedded with quartzofeldspathic petrofacies reflecting superposition of active volcanic activity. Geochemical analyses for major and trace elements provide useful provenance informations. The Zr/Sc vs. Th/Sc and Cr vs. Cr/Ni plots suggest that sediment recycling is negligible. The use of geochemical diagrams for tectonic setting discrimination confirmed, in most of the cases, the inferred tectonic setting, corresponding mainly to an active continental margin and subordinately to a continental island arc. The idea of a multidisciplinary approach has been represented by the successful attempt to use together the information provided by petrographic and geochemical analyses. Compositional data from Eocene-to-Oligocene sandstones of the Thrace Basin were used to unravel the interplay between tectonics and sedimentation by means of multivariate statistical methods adapted to the particular nature of the available data (concentrations and percentages). The biplot was particularly useful in order to extract details in terms of source area evolution. The indications obtained call for a progressive enrichment from mafic to felsic elements, corresponding to increasing rates of supply from deeper levels of the crust. In conclusion, petrostratigraphic (detrital modes) evolution and geochemical signatures of the Eocene-to-Oligocene sandstone suites of the western portions of the Thrace basin in Greece and Bulgaria is closely related to various geodynamic stages of the Rhodopian region, from collisional to post-collisional orogenic collapse and the superimposed volcanism related to extensional collapse. The type of sedimentary provenance of these Rhodopian Paleogene sandstones, provide an example of the changing nature of orogenic belts through time, and may contribute to the general understanding of similar geodynamic settings.
On the Danubian island "Pacuiul lui Soare", between 355 and 357 km, there are the ruins of a Byzantine fortress from the X-XIII centuries, most of which has already been eroded by the Danube river. A seismoacoustic survey which was carried out along the Danube in front of the island, showed the presence of the fortress ruins under the river waters. Further geo-archaeological survey is required in the studied area, aiming to a better understanding of the island evolution and of the fortress history as well.
The quality of environment is extremely important for the human society development as well as for the entire biosphere equilibrium. In order to decipher the real status of an extended (regional) area and to rapport the print image of the local areas - subjects of development projects, a geochemical investigation have been performed in the Bucharest-Ilfov Region (Romania). The environmental factors (soil, underground and surface water and plants) evaluation on local or regional scale finds in geochemical survey (sampling, analyzing, mapping and reporting to national/international qualitative standards) an adequate solution. Taking into account the necessity of evaluating and monitoring the intensive populated areas, the exigency of such operation on height qualitative standards and at low costs increases. Admitting the European criteria to evaluate the water, soil and plants quality preservation as reasonable and averaging between national standards of EU community, the first observation regards the lowest possible price of sampling (proportional with sampling density, and increasing in case of difficult field access) and the highest accuracy/detection limits of final qualitative database acquisition. The necessary analytical diversity for a complex environmental investigation exceeds the classical routine of geological-geochemical one (usually limited to metalogenetic objectives) and includes various sophisticated categories (organic). For example the pesticides (a widespread category of biocides) investigation is an example of mostly refined and expensive analytical imperative. A systematic sampling must be performed at densities that ensure the representativeness on small surfaces (at least 4 soil samples/km2, 1-2 underground water samples/km2, 1 surface water sample/km2, 2 samples of the same species of plant/km2) followed by physicalchemical analyses for specific categories (soil: As, Cd, Cr, Cu, Pb, Ni, Zn, Hg, mononuclear aromatic hydrocarbons and poli-aromatic hydrocarbons BTEX, PAH, insecticide organic chloride; vegetation: As, Cd, Cr, Cu, Pb, Ni, Zn, Hg; water: pH, conductivity, soluble oxygen, NH4+, NO2, NO3, PO4, Cl, SO4, Ca, Mg, Na, As, Ba, Cd, Cr, Cu, Co, Pb, Mn, Ni, Fe, Se, Zn, Hg, Te, Tl, Sn, U, V, phenols, BTEX, PAH, policlorurate biphenyl, organic-chloride insecticides. The mono-compound maps for each analyzed category were performed. Looking to the toxic and undesirable categories for each factor, lots of polluted areas have been identified as well as the pollutant sources.
In order to evaluate less expensive solutions and the most relevant/representative mapping, the sampled/analyzed data were gradually reduced. The successive maps were analyzed in order to establish the proper sampling density for each chemical category. The quality of the environmental factors on the studied territory was affected by the lack of protection–prevention measures during the communist economy expansion and the massive post communist abandon of the industrial and agro-industrial units and by various polluting activities. This territory is undergoing an intensive developmental dynamic, the most intense of the entire national territory. Besides, the lack of a preliminary evaluation of the qualitative stage and the geographical extent of the polluting phenomena influences the environmental factors and will affect directly and essentially the quality of human life and socio-economic development. The elaboration of the cartographic image on the environmental pollution/preservation (the main purpose of this paper) supports both the necessary protection/prevention measures and the future socio-urban and cultural development plans for the target area (Bucharest-Ilfov). Meanwhile, it validates the geochemical systematic investigation as the main efficient and accurate methodology in assessment of environmental status of an area.
The Thrace Basin is an important hydrocarbon province covering an area in excess of 15,000 sq. km in Turkey, Greece, and Bulgaria. The complex historical vicissitudes of the region have made collaboration among the researchers of the three countries difficult. Consequently, a unified and widely accepted geological interpretation of the Thrace Basin is still missing. Nevertheless, a great wealth of outcrop and subsurface data is already available from both academic and industrial sources. Integration of preexisting data (seismic and oilwell stratigraphy, geological-structural field maps) with new field mapping as well as new stratigraphic, sedimentologic, thermochronologic, petrologic, and radiometric data has provided significant constraints on the evolution of the basin.
The Thrace Basin developed during the complex transition between the collisional tectonic regime following the closure of Vardar-İzmir-Ankara oceanic realm and the extensional regime characterizing the Neogene evolution of the Aegean and periAegean regions. It was long interpreted as a forearc basin which developed in a context of northward subduction. This interpretation was challenged by more recent data emphasizing the lack of a coeval magmatic arc. The interpretation of the Thrace Basin as a forearc basin was also based on the occurrence, along its southern margin, of a belt of chaotic deposits interpreted as a tectonic mélange formed in an accretionary prism. However, this tectonic mélange may represent olistoliths in an Eocene sequence. All these elements along with the correspondence between subsidence pulses in the basin and lithospheric stretching in the metamorphic core complexes of southern Bulgaria and the northern Aegean region may indicate instead that the Thrace Basin was the result of either (i) post-orogenic collapse after the continental collision related to the closure of the Vardar ocean, or (ii) upper-plate extension related to slab retreat in front of the Pindos remnant ocean. Preliminary data indicate that initial subsidence (Ypresian-early Rupelian) was localized in small depocenters delimited by a system of strikeslip faults, probably during the late stages of collision. Further subsidence over a wider area occurred during the rest of the Oligocene, in agreement with the timing and areal distribution of crustal stretching phenomena evident during this length of time over the entire northern Aegean region. This hypothetical two-stage evolutionary trend might represent a predictive tool in the tectonostratigraphic interpretation of similar sedimentary basins.
Seismic sections across the central part of the basin and the tectonostratigraphic interpretation of outcrops in the Gelibolu Peninsula and along the Greek-Turkish border show that between the Middle Eocene and the Early Oligocene important east-west-trending transcurrent faults cut the Thrace Basin, generating a series of depocenters and uplifts which deeply influenced sediment dispersal and the areal distribution of paleoenvironments. In addition to the "flower" structures seen on seismic lines, strike-slip tectonism induced also abrupt temporal and areal variations in subsidence rates, as well as dramatic sedimentological facies changes within coeval stratigraphic horizons. Such strike-slip-dominated tectonic scenario during the late- and post-collisional stages related to the closure of the Vardar-İzmir-Ankara ocean is further corroborated by the presence of an important strike-slip shear zone of crustal relevance in the region just south-east of the Marmara Sea. Such shear zone is at least 225 km long, has an horizontal offset of about 100 km, and has a trend similar to the the present-day North Anatolian Fault. A similar shear zone- although poorly studied- occurs in the Kapidaği Peninsula south of Marmara Island. In addition, published thermochronological data demonstrate the existence of a praecursor of the North Anatolian Fault in the area of the present-day southern Thrace Basin active at least from the Oligocene.
The Middle Miocene (Badenian) celestite (sulphate) diamictites, genetically associated with Salt (Evaporite) Formation, occurs in the external last lineament of the Sub Carpathian Nappe.
The Middle Miocene is the stratigraphic correspondent of the early used term “Tortonian” of Vienna Basin and to present term “Badenian”. It has been firstly separated and described in Muntenia Sub Carpathians and comprises four lithobiostratigraphic horizons: the “Tuff and Globigerina Marls” horizon; salt breccias with salt bodies or “Upper Saliferous” horizon; “Radiolarian Schists” and “Spiratella Marls” horizon. These horizons have been recognized under the same name or under different names all over the Carpathians domain and moreover these “horizons” were recognized, with some exceptions, in the whole extra Carpathian area, Transylvania and Maramures.
In Vrancea area the “Salt Formation” or the “Evaporite Formation” is represented by gravelly-sandy, gipsiferous lithotype respectively the sulphate diamictite, by the haliticanhydritic lithotype and by the secondary carbonate lithotype, together being genetically related.
The components of gravelly-sandy deposits are bound by a brown-black, clayey matrix having with earthy appearance. The matrix is chiefly impregnated with bituminous organic matter and is considered to be an insoluble residue entrained from dissolving evaporite beds. Usually the matrix is dominating (matrix-supported texture) – ubiquitous feature observed especially in mines. In places the matrix could be absent (claste-supported texture), this being explained by removal due to meteoric leaching. Its high-degree of intercrystalline porosity makes it a potential subsurface reservoir for hydrocarbons or metalliferous solutions.
Referring to celestite-bearing ore on the Valea Sării-Andreiaşu lineament (Vrancea district) the author separated in outcrops and in the mine (along Valea Sării brook) three types of mineralizations – petrologically and mineralogically different, but displaying continuous transitions between them. These are:
Mineralizations having impregnation character (mudstone-celestite using Dunham’s, 1962 classification for carbonate rocks), in a matrix-supported fabric according to background/crystals ratio. This type is widespread, was separated in heavy minerals concentrates too. Also, it borders the massive type of celestite mineralizations and is characteristically closely related to gypsum and anhydrite. Also, it has been considered that the celestite appearing in evaporite sediments of an intertidal environment is primary or early diagenetic. It does not form accumulation of economic importance.
The second type is a massive mineralization of replacement character, a wackestone/packestone celestite, in a crystal-supported fabric. Other authors termed it as “blocky celestite” or “replacement-type celestite”. Under the microscope some peculiar euhedral to anhedral shape of turbid-like methasoms of celestite, with a lot of inclusions and syntaxial rims showing an “intersertal texture” evidently disturbed by lack of space could be seen. The hot-rock within multiangular space between crystals is subordinated. This type has been developed during diagenetic stage as a true irregular and concretionary celestite bearing ore by redistribution of materials within sediment (diagenetic metasomatism).
The third type is a secondary mineralization, known as “celestite infilling cavities and fractures”. This type has been developed in a free space, with syntaxial rims and without inclusions and no host rock. It is white colored, in large fan-like or fibrous or long prismatic crystals or in collomorphous aggregates associated with sulphides. During epidiagenesis stage involving uplift and sub aerial exposure of diamictites as is observed on Valea Sării and Reghiu brooks – the evaporite re-enter in active phreatic zone and a secondary mineralization may develop.
The sedimentologic characteristics of coal-bearing Oligo-Miocene deposits occurring at the north of İstanbul have been examined in this study. The study area in Thrace Basin includes coal formations in deltaic deposits of Oligo-Miocene age. Coal-bearing deltaic deposits in this field have been evaluated in the Danişmen formation and the coal bed has been extensively exploited by open-cast methods.
The Danişmen Formation overlies the Eocene-Oligocene Ceylan Formation unconformably and consists of mudstone, sandstone, conglomerate and coal. It is unconformably overlain by the Pliocene deposits. Coal-bearing succession is composed of fining-upward interbedded facies. Five facies were identified in Coal-bearing sediments. These facies are; bedded conglomerates, thick bedded sandstones, organic rich grey mudstones, red mudstone and coal. These facies characterize delta plain deposits. The coal of the Danişmen Formation was deposited in swamps of delta plain. The coal bed in the Danişmen Formation has a thickness of 7.80 m, and the coal rank is of a lignite stage (soft brown coal).
The Yeniköy area in the Thrace Basin includes coal formations in deltaic deposits of Oligo-Miocene age. Coal-bearing deltaic deposits in this field have been evaluated in the Danişmen Formation and the lignite bed has been extensively exploited by open-cast methods. The lignite bed in the sampling point has a thickness of 7.80 m, and 9 profile samples were collected, from bottom to the top. The samples have been subjected to some analyses using standard methods. The coal samples, on an air-dried basis, average 11.02% moisture, 10.43% ash, 43.21% volatile matter, 35.34% fixed carbon, 1.93% total sulphur and 5221 kcal/kg net calorific value. The mineral matter of the selected coal samples that was identified by X-ray powder diffraction and SEM-EDX shows that the samples are mainly made up of clay minerals, quartz, and pyrite. The most abundant maceral group of the samples is huminite in which textinite, ulminite, and especially densinite are rich. Liptinite group macerals in all the samples, which are considerably higher than the inertinite group macerals. Elemental concentrations, which were determined by ICP-AES and ICP-MS, and Hg concentrations by Leco AMA254, have been evaluated in this study. The random reflectance values (%Rr, oil) of ulminite were measured in all the samples for the determinaton of coal rank, and the mean values of % Rr of ulminite indicate that the coal rank is of a lignite stage (soft brown coal).
This paper focuses on surface movements determined by geodetic methods and occurred as consequence of brine extraction from Tuzla salt deposit (Bosnia and Herzegovina). Previous studies were mainly concentrated on vertical movements, but important information about behavior of the deposit is also available from horizontal movement data. In the case of Tuzla salt deposit the geometry and spatial location of leached/empty spaces are unknown and the comparative analysis of vertical and horizontal movement could be really significant. The spatial identification of points with high values of vertical and horizontal movements depends on the geometry of empty spaces. Investigation of horizontal movements has been carried out analyzing data collected by several geodetic measurements. The results obtained by the correlated spatial analysis of vertical and horizontal movements, can identify basic geometric characteristics of the leached/empty spaces. The discussed temporal intervals are two characteristic periods, reffered to the capacity of the deposit exploitation. Movement rates per year and correlation between horizontal and vertical movements are considered as indicator parameters defining the character of ground deformation. Spatial analysis of these coefficients values has identified high risk areas, and gives additional information in thegeological structures definition.
The paper treats the possibilities to recover the waste from coal combustion in some power plants in Romania. The greenhouse gas and the ashes have a huge impact on environment and the living species. The using of ash – recovered wastes – induces decreasing of the demand of natural resources. They also reduce the energy - intensive production of other concrete ingredients, leading to energy saving and decreasing the “greenhouse gas” emission. Replacing one tone of cement with fly ash it would save enough electricity to power an average home for 24 days, and reduce carbon dioxide emissions equal to a two months use of an automobile.
During the study, in the experimental work were compared the properties of five different compositions of masonry mortars were prepared replacing the cement with different amounts of ash. The setting time and the workability were determined on the fresh mortar. After 28 days of hardening in standard conditions (5 days in moulds at 20°C and 90% humidity; 2 days without moulds at 20°C and 90% humidity; 21 days without moulds at 20°C and 65% humidity) the density and water absorption of the mortars were determined using the methods indicated in the European standards. The flexural and compressive strength of the compositions were determined after 28 and 56 days of hardening.
The fresh and hardened mortars characteristics were investigated. The compositions (cement, Zalau ash, sand and water, in different proportions) were prepared by forced mixing using a laboratory mixer. The fresh mortar was cast in metallic moulds obtaining 160x40x40 mm prisms which were subjected to testing in hardened state.
The study demonstrated that it is possible to use ashes in the mortar compositions, by replacing a part of the cement by ashes. The replacement of cement in proportion of 5, 10, 20 and 30 wt% was experimented. Thus, the setting times of the mortars increases. The difference between the initial setting time of the composition without ash and the composition in which 5 wt% of cement was replaced by ash is only 5 minutes. The differences are bigger for higher ash content; it reaches 80 minutes for composition 5 in which 30 wt% of cement was replaced by ash.
The differences are more evident in the case of the final time of setting, where replacement of 5 wt% cement lead to a 30 minutes longer final setting time and replacement of 30 wt% cement with ash a 310 minutes longer time, which means an increase of 1,5 times.
In the case of mortars workability no differences were observed between the composition with no ash and the composition in which 5 wt% of cement were replaced, after that every 10wt% of cement replaced by ash brings 5 minutes in plus.
The density increases slowly by replacing 5% of cement, after that a decrease is observed, every sample densities being under the density of the standard composition. The water absorption is in agreement with the results obtained for the densities. The water absorption decreases from 8.96 % (in the standard composition) to 8.34% (for composition 2 with 5wt% ash). For the other compositions the value of absorption increases to 12.87%, while the ash proportion was increased to 30 wt%.
The values for the mechanical strength state the observations at the density and absorption determination. For the composition with 5 wt% ash was observed an increasing of flexural and compressive strength. While the ash content was increased the mechanicalstrength decreased and it is situated below the standard composition strength. The mechanical test after 56 day of hardening shows that the strength increase is higher for the compositions with ash.
It can be concluded that the Zalau power plant ash can be used in mortar compositions 5 wt% replacement of cement by ash brings both economical and qualitative benefits.
The present paper refers to the major part of the Egnatia highway, about 100 km long, which connects Thessaloniki and Kavala cities in North Greece. Actually, it is divided in three parts: i) Nymphopetra-Asprovalta, about 40 km long, ii) Asprovalta-Strymonas, about 20 km long and iii) Strymonas-St. Andreas, about 40 km long. The highway has already been constructed. Driving from the west to the east, the highway, at the beginning of Nymphopetra-Strymonas part, passes nearby Volvi lake, at the foot of Vertiscos Mountains. Easterly, it passes through Kerdillia Mountains, Strymona’s river and it leads to Pangeo’s mountain, ending through Symbol Mountains. The highway also passes through five tunnels; i) Vrasna tunnel, which is located at Nymphopetra – Asprovalta’s part, ii) Asprovalta’s tunnels, which are three tunnels locating at Asprovalta – Strymona’s part and iii) Symbol tunnel, which is located at the last Strymonas – st. Andrea’s part. The paper describes the support measures against geological failures during the construction of the highway. For this purpose, the mechanisms of sliding and rock falling procedures were studied. As far as slopes concern, the orientation of the discontinuities and the poor quality of the rock mass, that creates cyclic sliding, were responsible for the instabilities. Rainfall also helps landslides to be occurred. During the tunnelling excavation, the sliding along a plane, the décollement from the roof and the fall of wedges were the common failure causes.
Aghios Konstantinos lies on the foothills of the Atalanti fault system scarps. The area is located in central Greece and the fault system is the primary morphology-controlling agent. It defines the west shoreline of northern Euboea gulf and is associated with several historical earthquakes.
Morphologically this zone forms steep high bedrock scarps, on the foot of which extensive colluvial deposits are observed. Several minor fault scarps have been mapped and they were classified in three classes: a) bedrock fault scarps with visible fault plane, b) softsediment scarps with visible fault plane and c) soft-sediment scarps with no visible fault plane. The minor scarps are generally aligned in en échelon pattern, following the general WNW – ESE trend of the major fault zones, while their general dip direction is towards the NNE. Fault analysis shows that there is extensive tilting of hangingwall blocks, as well as of the minor faults themselves. Faults tend to “lock” with each other forming a complex pattern that is inherited to the overlying Upper Miocene-Pleistocene and Holocene sedimentary cover.
A small settlement was found at “Karvouna” site, west of Aghios Konstantinos, during the works performed for the construction of a new segment of E75 highway. This settlement comprises of low-lying houses, storage rooms and a small temple. A larger and more important temple was discovered in another location nearby. According to archaeological evidence, the settlement was active in classical and Hellenistic times, and sporadically afterwards. It was a rural settlement and numerous finds indicate at least three successive layers of buildings with stone foundations criss-crossing one another with no particular pattern.
The foundations of the buildings and the surrounding environs show many signs of episodic deformation, either direct or indirect. The most obvious cases are:
A surface rupture cutting through at least two foundations. It has a heave of up to 3 cm and a slight normal displacement.
Several basal walls and foundations have been found tilted and deformed. Tilting is as high as 30º off vertical.
A small temple that is located just outside the settlement shows signs of sudden destruction: roof tiles are being found in and around the temple. They are roughly retaining the space that they had on the roof, which is an indication that the wooden roof collapsed. Also, one of the entrance pillars seems displaced both vertically as well as left-laterally. This displacement vector is compatible with the general fault displacement vector in the area.
An artificial cross-section at the stream that bisects the settlement shows an exposure of a normal fault system that deforms a series of paleoseoils and runs through the settlement, parallel to the main fault. Paleoseismological analysis of the cross-section shows that this fault system was not active in historical times, although the southwesternmost strand of the system roughly coincides with the surface rupture.
The position of the settlement on a rather steep slope, as well as the nature of finds, indicate a severe topographical amplification of the effects. Nevertheless, we believe that the primary deformational cause was faulting, evidence of which has been found in the crosssection that was consequently amplified by gravitational effects.
Faults in urban areas pose a real danger for buildings and infrastructures, not only in the case of an earthquake, but also in such cases as differential sediment compaction, water overpumping, etc. Their importance is often underestimated with sometimes severe consequences.
Detection of faults is not easy in urban environments, as usually outcrops have been covered by built structures, prohibiting direct observations. Geophysical surveys are rare, but even in those cases the exact location of a surface-intercepting fault is not clear.
One of the most promising methods for acquiring quantitative information about faults in urban areas is paleoseismological investigation. It consists of an integrated set of methodologies that can provide hands-on data for displacement, timing, etc. In this paper we present two cases of paleoseismological applications in the metropolitan area of Thessaloniki.
Two faults, one evident and one unknown, have been studied in Peraia and Kalamaria respectively.
Peraia fault: This fault defines the contact between the footwall Pliocene sandstonemarl series and the hangingwall loose Holocene deposits. It is a fault that coincides with the well known Anthemountas fault zone, a roughly E-W trending normal fault zone that is associated with several historical earthquakes. Its exact location through Peraia town was not known in much detail due to the lack of outcrops. Nevertheless, it forms a well defined scarp that divides the town into an upper (Ano) and lower (Kato) part. In 2005 and 2006 a set of surface ruptures along this fault caused significant damage on buildings and roads. Paleoseismological investigation with two trenches along the fault showed that faulting was not random, as a large displacement was detected, with successive steps of cumulative faulting. Borehole data confirmed that the total displacement was indeed large (35 m). Trenching showed that the fault has been continuously active during the Quaternary, with all of its displacement on the same surface, posing thus a severe danger for the area in general and specifically for the buildings that are built along its trace. The 2005-06 surface ruptures are interpreted as a combination of overpumping, compaction and fault creep. The contribution of each factor is not possible to be calculated, as there are too many uncertainties concerning the deformation model.
Kalamaria fault: This fault was exposed during the construction of a multi-stored residence building in Kalamaria, a town located next to Thessaloniki city. This fault is displacing marls and a paleosoil that is located on top of the sedimentary sequence. Morphologically it is manifested as a gentle scarp, observable in roads that cut through the fault along at least 500 m. Paleoseismological analysis showed that the fault has been inactive during Upper Pleistocene – Holocene as there are no indications for recent reactivations. However, the existence of the morphological scarp suggests that it has probably been active during that period, but microstratigraphical evidence for this activity has been destroyed by anthropogenic factors. Even if it is not active, the fault zone exists and it can act as a weakness zone during a distant earthquake or in response to water level fluctuations.
In conclusion, paleoseismological techniques can be of great effectiveness in the study of urban faults, either active or not. Planners should take into account this methodology, because it can greatly enhance the understanding of ground response in abnormal conditions.
Coastal erosion is a gradual process that alters the distribution of sediments and modifies the geomorphology of the coasts. It may result in the destruction of natural coastal defences (sand dunes, cliffs, etc) and the increase in land instability which may in turn result in flooding of the hinterland and landsliding of coastal areas with steep slopes and unstable materials. The damages induced by such hazards include loss of life, property, infrastructure, and land. The costs of emergency action, remediation and prevention can often represent a significant burden to the communities affected and to national governments. According to predictions, climate change impacts, including sea-level rise and extreme weather patterns, will lead to the increase in the frequency and intensity of such hazards. Risk-based decisionmaking is seen to provide the means of addressing the challenges put forward by climate change. The complexity and interrelation of the processes acting on coastal locations call for an integrated framework for the assessment of coastal risks and the identification of the appropriate measures for the prevention and reduction of erosion, flood, and landslide risks. In this paper, existing models for the mapping of pressures on coasts and current development practices and tools will be reviewed, before a holistic methodology is proposed in order to assist decision-makers in effective coastal risk management.
Migmatites of proved Paleocene-Eocene age are widespread in several tectonic units of the Rhodope metamorphic complex (RMC). Most of the migmatitic unit precursors consist of orthogneisses. These were predominately felsic rocks of granite to granodiorite and diorite composition of late-Paleozoic (Arda unit) and late-Jurassic protolith ages (Madan, Startsevo, and Chepinska unit). Zones of post-anatectic extension outline the unit boundaries obscuring the melt-in isograd in the RMC. The peak metamorphic conditions correspond to kyanite sillimanite transition at 650 - 700ºC / 0.6 – 0.8 GPa. The most common thermobarometric estimates are close to the water-saturated granite solidus in sillimanite stability field. The absence of clearly distinguished residuum and peritectic anhydrous minerals indicate fluidassisted melting of metagranitoid precursors. Field observations distinguish metatexite and diatexite structural types. The metatexites occur in all migmatitic tectonic units. The diatexites occupy large domains in the Arda and Chepinska unit suggesting advanced melting within cores of regional thermal antiforms flanked by metatexite. The common constituents of metatexite sections are concordant to the foliation in situ leucosome ± melanosome, and mesosome. Discordant leucosomes fill decimetric scale shears and form vein-network together with concordant leucosomes, marking a transition to structurally disrupted diatexites. The latter include subautochtonous lens-like bodies and sheets of inhomogeneous granite. The mesoscale interconnected structures indicate syn-deformation melt flow. Different mechanisms of melt transfer resulted in injection of melt batches into metatexite and subsolidus sections of the RMC.
The rock-forming mineral assemblages comprise biotite, plagioclase, K-feldspar and quartz, plus amphibole in metagranodiorite and metadiorite mesosome, or muscovite in some diatexite (Arda unit). The leucosome is quartz-feldspar dominated and differs from mesosome and particularly from melanosome with lower mafic and accessory mineral proportions. Scarce amphibole-bearing leucosomes resulted from back-reactions between migrating felsic melts and refractory amphibole-bearing rocks. The normative mineral ratios span tonalite to granite field in mesosomes, and trondhemite to granite field in metatexite leucosomes, whereas granite bodies from diatexite domains correspond to low-temperature granite melts. The uniform accessory mineral assemblage includes: magnetite, zircon, allanite, apatite, ± titanite in metatexite; and magnetite, monazite, ± xenotime, ± garnet in diatexite. Inherited protolithic zircons dominate both metatexite and diatexite, while new Paleocene-Eocene zircon is scarce. The low temperature melts had little or no impact on dissolution and growth of zircon, however they were responsible for partial dissolution of allanite and apatite, and subsequent crystallization of Paleocene-Eocene monazite.
The geochemical features corroborate fluid-assisted low-temperature melting of felsic minerals and limited solubility of accessory phases in the melt. The felsic products of migmatization are depleted in Fe, Mg, Ca, HFSE (Zr, Hf, Nb, Ta, Th, and U), Y, and REE. The contents of Zr and LREE cluster close to felsic peraluminous melts saturation at 650 - 750ºC. The REE patterns display general depletion, strongly variable LREE/HREE ratios, and Eu/Eu* ≥ 1 in leucosome and anatectic granite bodies. The systematic compositional changes in the succession concordant leucosomes - discordant leucosomes - subautochtonous granite bodies reflect anatectic melt fractionation and emphasize the most incompatible LILE enrichment during anatectic melt migration and crystallization: increasing LILE/HFSE, K/Ba, and Rb/Sr, and decreasing Ba/Rb ratios; positive correlation between K/Rb and Eu/Eu* values of anatectic granite bodies. The elements ratios between the HFSE remain relatively unchanged overlapping mesosome ratios variation. For that reason the products of migmatization and precursors plot on the same fields of the discrimination diagrams and illustrate this way inheritance of geochemical features related to HFSE mainly.
Acknowledgments. This study was supported by the Bulgarian National Scientific Fund grants DO 02-327 and DO 02-363.
In the Argolis, the Basal Sequence constituting the eastern Pelagonian margin which bordered the Vardar–Meliata oceanic domain, includes Late Triassic–Early Jurassic shallowwater carbonates, condensed pelagic limestones of Early–Middle Jurassic age, Late Jurassic radiolarian cherts, siliceous mudstones and sandstones rich in ophiolite fragments. Upsection, coarse breccias, also with clasts of boninites derived from a nearby ophiolite obducted onto the Pelagonian margin in Late Jurassic–Early Cretaceous times crop out.
Along the road from Angelokastron to Sofiko, about 2 km east of the village of Angelokastron, a small quarry exposes pervasively sheared dark reddish-brown, radiolarianbearing cherty shales with disrupted fragments of chert and chert nodules impregnated by ferro-manganese oxides. These shales occur in the footwall of a thrust bringing them into contact with the Pantokrator Limestone of the Basal Sequence.
We collected more than 30 samples of the nodules and the shaly matrix. 13 nodules and one matrix sample yielded determinable radiolarians. 16 x-ray fluorescence analyses were carried out on 12 nodules that indicated a hydrothermal origin of the ferro-manganese mineralization.
The radiolarian taxa found indicate four age groups for the nodules that are embedded in the siliceous shale matrix that yielded a Middle Jurassic age (middle Bathonian). The first group includes nodules of Late Triassic age (late Norian–Rhaetian); the second group nodules of Early Jurassic age (early Pliensbachian and probably middle–late Toarcian); the third group nodules of early Middle Jurassic age (Aalenian–Bajocian); the last group finally includes nodules of late Middle Jurassic age (Bajocian–Bathonian).
The presence of Late Triassic to Early Jurassic Mn-impregnated chert nodules in a Middle Jurassic matrix indicates a deep oceanic environment prior to the tectonic emplacement of the succession onto the Pelagonian continental margin. We suggest that these nodules, more lithified than their matrix, were exhumed on the slope of an intra-oceanic accretionary wedge and were redeposited in the Middle Jurassic siliceous mudstones on the floor of the remnant Vardar–Meliata Ocean.
The Koziakas massif, located at the western boundary of the Thessaly plain, consists of a stack of thrust units emplaced westward onto the Pelagonian (s.l.), which in turn thrusts onto the Eocene Pindos Flysch. The dismembered units of the Koziakas are unconformably overlain by the Oligocene-Miocene molasse of the Mesohellenic trough.
In the Koziakas massif, at the top of the “Pelagonian” succession, three ophiolitic tectonic units crop out:
a) the “Mélange and Fourka Units”. At the base of the Fourka Unit scattered outcrops of ophiolite-bearing mélange are exposed. The Fourka Unit consists of thrust sheets and blocks of pillow lavas locally covered by radiolarian cherts.
b) an “Ophiolite Unit”, consists of slivers of sheared serpentinites, locally containing dunite bodies, plagiogranite and boninite dykes.
All volcanic rocks studied herein come from the “Fourka Unit” and consist of basalts and basaltic andesites. Six samples display a clear alkaline affinity and are similar to the alkaline within-oceanic plate (WPB) and are interpreted to have generated in a seamount setting. Two samples display similarities with enriched MORB (E-MORB) and are interpreted as formed from a N-MORB type mantle source slightly enriched in a plume component during the early stage of oceanic spreading or in an off-axis oceanic setting.
We examined 32 samples for radiolarian analyses. The assemblages of the samples collected near the WPBs indicate Middle and Late Triassic age, while the radiolarites collected near the E-MORBs indicate Late Triassic age.
The occurrence of Late Triassic WPBs and E-MORBs points to the existence of an oceanic setting in which the N-MORB asthenospheric source was influenced by a plume-type component and resulted in the off-axis eruption of enriched alkaline basalts and enriched MORB-type basalts. This conclusion is in agreement with similar results obtained from other sectors of the Hellenide ophiolites. During the post-Late Jurassic compressive tectonic phase, which affected the Internal Hellenides, the Mélange and Ophiolitic Units tectonically overthrusted the “Pelagonian” continental margin represented by the sedimentary units of the Koziakas Massif. During the post-Late Eocene compressive tectonic phase all these units were refolded and thrusted southwestwards onto the Eocene Pindos Flysch.
Fissured and karstified Eocene and Mesozoic carbonate formations of the Podhale Basin represent the largest reservoir of renewable thermal waters in Poland. They outcrop in the Tatra Mts. at altitudes of 1 000-1 800 m and deep to the north under the flysch formations of the basin. The main direction of flow is to the north for abt. 15 km where the impermeable formations of the Pieniny Klippen Belt divides it and diverts to the west and east, and next to the south to the Danube watershed in Slovakia. The temperatures range from abt. 20° C near the outcrops to abt. 85° C at the most northern wells. For a better understanding of the flow pattern, environmental isotopes (δ18O, δ2H, 3H, 14C, δ13C) have been used since early seventies and recently also gaseous tracers (He, Ne, Ar and SF6) under the grant No N 525 402334 from the Ministry of Science and Education.
The C14 data of thermal waters change from 37 to 0 pmc with δ13C from abt. −5 to 0‰; exhibiting the influence of isotopic exchange with carbonate minerals, which makes the quantitative dating difficult. The δ18O and δ2H are similar to those of modern waters in springs and wells with cold water, with several exceptions characterized by shift of δ18O to heavier values, which are caused by isotopic exchange with carbonate minerals. The isotopic altitude effect was estimated form the data of springs and wells within the Tatras area. For δ2H, the mean altitude of recharge area reads: h2 (m a.s.l.) = −69.1⋅δ2H − 4054, with the uncertainty of about 100-200 m. The most negative δ2H values of thermal waters are similar to the values observed for large karstic springs in the Tatras, which may suggest their Holocene age. However, the spatial distribution of δ2H values indicates that close to the recharge area, the thermal waters are similar to those of medium springs discharging at the lowest altitudes. Thus, the most negative δ2H values of thermal waters observed far in the basin most probably result from recharge under cooler climatic conditions. Very high He excess contents and negative noble gas temperatures (NGT) derived from Ne and Ar
concentrations are in agreement with such interpretation. The lack of 14C and δ13C values close to 0‰ in these wells also confirms that hypothesis.
Tracer data indicate the presence of the oldest waters in the north-eastern part of the basin whereas in the western part the exchange of water is faster by one to two orders of magnitude. That unexpected flow pattern most probably results both from the presence of some karstic channels in the western part, which enhance regional permeability, and from obstacles to horizontal flow caused by fault zones in the eastern part.
The Xanthi Plutonic Complex (XPC) is one of a series of Oligocene subduction-related plutonic bodies comprising an “acid” group and a “basic” group. Based on mineral compositions and assemblages of the “basic” group, the XPC is assumed to have originally crystallized at a pressure of 5.4 kbar and at a temperature of 1300oC under relatively dry conditions and oxygen fugacity (fO2) near the NNO buffer. As the basic magma migrates to shallower levels and at a temperature of about 870oC, water content increases and oxygen fugacity moves towards the MH buffer. The increase of water content could be the result of open system evolutionary processes. The “acid” group crystallizes at an average temperature of 729oC and at a pressure of 0.7 kbar under oxidizing conditions, between the NNO and MH buffer, suggesting a possibly different origin and/or evolution for the “acid” group.
UV radiation can have both positive and negative influence on human health. According to the classification of biological UV resources proposed by Chubarova (2007) we define favourable UV conditions as the conditions, when it is possible to get vitamin D3 at noon within an hour but when at the same time the UV index does not reach the high UV category. Different methods were used to estimate the thresholds for generating the vitamin D3 in the skin. One method was based on the approach, which has been proposed by Holick and Jenkins (2003), and another one was based on the recommendations given in the CIE 2006 publication. We compared both approaches by evaluating and comparing the year periods with the conditions favourable for vitamin D3 production. The periods were obtained through the calculation of biologically active irradiance using the TUV model with the 8 stream DISORT solver, and some other modifications described in Chubarova (2006). According to our estimates in midlatitudes the application of the second method leads to the increase in day number (approximately 18 days), when it is possible to get the vitamin D3 in clear sky conditions. It is necessary to emphasize that this difference takes place mainly due to the different thresholds of the skin exposure area recommended in these approaches, since both erythemally-weighted and vitamin D3 irradiance have similar absolute values at noon in spring and autumn, when a “jump” from unfavourable to favourable conditions and back for vitamin D3 production occurs. We have also revealed a large difference in sensitivity of erythemally-weighted and vitamin D3 irradiance to the changes in solar zenith angle, total ozone content (especially, at high solar zenith angles), and quite similar aerosol influence on both types of biologically-active irradiance. Using the updated criteria for vitamin D3 threshold from CIE 2006 we estimated the biologically active UV irradiance over northern Eurasia. The spatial and seasonal distribution of UV favourable conditions has been analyzed both for the clear sky and for the cloudy atmosphere. The calculations were based on the TOMS/OMI total ozone and effective UV reflectivity datasets. The latter one has been used for estimating the effective transmittance in cloudy conditions. The aerosol parameters necessary for computations were taken from a specially developed aerosol climatology, which has been obtained on the base of ground-based AERONET dataset, radiometric Russian datasets and satellite MODIS retrievals (collection 5) over northern Eurasia. A special attention was paid to estimating the uncertainties of MODIS AOT dataset. We found the large AOT biases in spring conditions over Siberian area. The specific features of the defined favourable UV conditions for different time periods are discussed for the various types of human skin in the clear and cloudy atmosphere.
Acknowledgments: The work was partially sponsored by RFBR Projects #10-05-01019 and #09-05-00582.
The oldest olistostromes in the Outer West Carpathians are related to the Late Jurassic-Early Cretaceous rifting and post-rifting stage in which the Outer Carpathian deep sea sedimentary basins were opening. Then forming the proto-Silesian Basin later was split into separate tectonic units – Silesian and Subsilesian nappes. In the Silesian Nappe the oldest deposits are represented by the Vendryně Formation (Late Jurassic) that consists in many places of clasts and olistolithes of shales and marls. The Hradište Formation (Early Cretaceous) often bears debris-flow deposits rich of exotic-rock pebbles, but also olistostromes with olistoliths or olistoplaques of the Cieszyn and Vendryně formations.
In the Late Cretaceous – Paleocene took place a contraction. It was a formation time of subduction zones along the active margins and development of deep-marine flysch basins. The Magura, Dukla, Silesian and Skole basins have been formed then. Ridges separated them supplying the basins with huge amounts of coarse-clastic material marked by numerous debris-flow sediments and occasionally olistostromes and levels with huge olistoliths. They occur in the Upper Cretaceous, Paleocene and Eocene strata of the Silesian, Subsilesian and Skole nappes. Specially known are large olistholits of the Węgierka from the Upper Cretaceous deposits of the Skole Nappe Marls and the Frydek Marls with huge blocks of andesites and pebbles of other exotic rocks from the Subsilesian. In the Silesian Nappe the debris-flow with flysch olistolites and exotics are frequent within the Godula and Istebna Beds (Late Cretaceous –Paleocene), the Ciężkowice Sandstones (Early – Middle Eocene) and occasionally within the Hieroglyphic Beds (Middle – Late Eocene). The Middle Eocene olistostromes are known also from the Bystrica and Rača subunits of the Magura Nappe.
A collision of the European Platform with the Inner Carpathian terrain took place in the Oligocene and Early Miocene stage causing a development of the Outer Carpathian accretionary prisms. Evolving prism supported olistolithes and olistostromes to the basins until their structural closure. Especially in the inner part of the Silesian Nappe the Krosno Beds (Oligocene – Early Miocene) are rich of olistoliths and in some places olistostomes with large olistoplaques occur. Olistostroms at the top of the section of the Krosno Beds has finished sedimentation in the Silesian Beds. In the western part of the Subsilesian Nappe section of the Krosno Beds is ended with olistostrome rich of huge olistoliths of the Jurassic,Cretaceous and Palaeogene rocks as well as older crystalline. There occur spectacular blocks of Jurassic limestones forming the klippes of Andrychów, Pavlovske Kopce and Štramberg.
During the Miocene tectonic movements caused final folding of the basins’ fill and created several imbricated nappes. The nappes are thrusted one upon another and all together overthusted the marine molasses of the Carpathian Foredeep developed on the North European Platform. From thrusting nappes large olistoliths glided down into the foredeep. Recently they are known from deep boreholes from bellow of the nappes. In front of the thrusting Outer Carpathian the molasses of fordeep were partly folded. It occasionally caused the formation of olistostromes, e.g. the Badenian evaporites known from the salt mines of the Wieliczka and Bochnia.
Acknowledgments: This research has been financed by Ministry of Science and Higher Eeducation in Poland, grant no N N307 249733.
The early stage of basin formation in carbonate platform settings, from rifting to further crustal thinning, is generally characterised by mass movements from the faulted margins towards the stretching and drowning sectors. Avalanches, debris flows deposits with extrabasinal blocks, olistoliths, olistoplaque and olistostromes mark the sedimentary record. Block tilting, related to the normal activity of faults, determines the uplift of basin margins, shedding material for the formation of oliststromes. The onset of basin dynamics could be also marked by magmatic upwelling. During the late rifting stage, mass movements decrease, sediments supply with huge olistoliths and olistostromes is less common and coarse-grained deposits prevail, alternating with periods of pelitic sedimentations. Such sedimentary evolution may be observed in several basin successions, independent of their age and geodynamic setting. Good examples are the Northern Carpathian Basin and the Sicilian carbonate platforms-basins system, compared here because of their similarities.
During the Late Jurassic-Early Cretaceous, the Southern European Platforms system topped by carbonate sedimentation experienced rifting and that resulted in opening of the proto-Silesian Basin. Crustal stretching was accompanied by andesitic-teschenitic intrusions. The Late Jurassic-Early Cretaceous sequences of the proto-Silesian Basin were later split into different tectonic units. Neritic grey, black or brownish marly mudstones deposited during the Kimmeridgian-Tithonian were locally associated with debris flows containing olistoliths derived from the adjacent carbonate platform. The mudstones evolve during Tithonian-Berriasian into pelagic limestones and shales with a complex of turbiditic limestones, suggesting a relatively quiet tectonics. Starting from the Valanginian, turbiditic and conglomeratic sandstones with exotic blocks appear within the calcareous shales. Locally, huge olistostrome appears, containing both extrabasinal olistoliths as well as olistoliths derived from the faulted flanks of the proto-Silesian Basin. These coarse sediments evolve upwards to Hauterivian-Aptian black shales. At the end of early Cretaceous (Barremian- Albian), compressional movements started, increased tectonic activity begun and uplift initiated denudation of the margins and ridges and resulting in very thick-bedded sandstones, conglomerates and occasionally olistoliths deposited during Late Cretaceous and Early Paleogene. An oblique collision of the Inner Carpathian terranes with the North European Plate during the Late Eocene-Early Miocene led to the development of accretionary prisms of the Outer Carpathians; numerous olistostromes were formed during this time.
In Sicily, the onset of basin opening (Imerese-Sicanian) occurred during the Triassic. It was interposed between carbonate platforms (Panormide-Hyblean-Pelagian). In the basal deep-water sediments, lenses of olistostromes with olisholiths and basaltic extrusions related to crustal stretching were deposited at the basin margins. These olistoliths were derived from mass-wasting of the Late Permian-Lower Triassic carbonate platform. Late Triassic sedimentation (pelagic marls and limestones) suggests relatively quiet tectonic activity, followed by increased crustal stretching, as suggested by olistoliths of Lower Triassic clastic limestones embedded upwards. Jurassic-Early Cretaceous sedimentation is represented by deep-water siliceous marls and radiolarites, containing several horizons of carbonate turbidites and breccias derived from erosion of the fault-controlled basin flanks. From the beginning of Late Cretaceous, deposition of basin-plain marls and limestones indicates the mature stage of basin dynamics. Upward in the succesion, thick horizons of resedimented carbonate breccias are very common, indicating the onset of tectonic inversion, from preorogenic extension to the chain building.
Acknowledgment: This research has been partly financed by the Ministry of Science and Higher Eeducation in Poland, grant no NN307 249733.
The Jurassic ophiolites in Albania are characterized by several mineralization types including chromites, Fe-Ni-Cu sulfides and arsenides, Fe-Ti-minerals and minerals of the Platinum Group Elements (PGE). Pentlandite-bearing mineralization is related to upper mantle serpentinized harzburgites, chromitite deposits associated with upper mantle dunites, dunites of the supra-Moho zone, ultramafic-mafic intrusions (wehrlites, lherzolites, pyroxenites and gabbros) and to cumulate layered sequences of olivine-gabbros and gabbronorites. Pentlandite occurs in several mineral associations including Ni-bearing sulfides, Fe-Ni-Cu-Co-PGE-bearing sulfides and chromite + Ni-bearing sulfides + PGM. It accompanies chromite, olivine, pyrrhotite, chalcopyrite, cubanite, magnetite, native copper, valleriite, mackinawite, heazlewodite, millerite and PGM. The chemical composition of pentlandite (metal: sulfur ratios, Fe:Ni ratios and Co and PGE contents) is variable depending on the geological setting, mineral associations and textural relationships. It is suggested that the pentlandite-bearing mineralization hosted within chromitite deposits, related to upper mantle dunites and dunites of the supra-Moho zone, is of primary magmatic origin, but the one hosted within upper mantle serpentinized harzburgites, ultramafic-mafic intrusions and to cumulate layered sequences of olivine-gabbros and gabbronorites is genetically related to hydrothermal activity combined with serpentinization processes, which played an essential role for the remobilization of some elements from the host rocks and the transformation of primary sulfides and PGM.
Although the first dinosaur discoveries from the Transylvanian Basin were made at Bărăbanţ near Alba-Iulia as early as the end of the 19th century, the Latest Cretaceous Transylvanian dwarf dinosaurs gained their worldwide notoriety only after Baron F. Nopcsa reported his first discoveries in the Haţeg Basin. Nopcsa realized the dwarfing tendencies of these dinosaurs and related this tendency to their limited environment, which he called “the Haţeg Island”. In order to defend the pattern he identified, he attempted to outline the spatial extension of this island, as supported by the distribution of illustrative non-marine sedimentary deposits. In this context, he discovered several new localities with dinosaurbearing rocks. Among these, the most important ones are located in the Alba-Iulia area. These faunal assemblages seem to be coeval with those from the Haţeg Basin. The non-marine Maastrichtian deposits from Alba County accumulated after the Late Cretaceous “Laramian” tectogenesis, when a fluvial system evolved in the area of the present-day Carpathians. As a matter of fact, the sediments exposed in Alba County suggest similar environments to those from the Haţeg Basin. In the red mudstones and the channel sandstones of the Şard Formation, several vertebrate teeth and bones have been preserved. In this paleobiota, dinosaurs are well represented by the following taxa: titanosaurian sauropods, the basal hadrosaurid Telmatosaurus transsylvanicus, the euornithopod taxa Zalmoxes shqiperorum and Z. robustus, the nodosaurid ankylosaur Struthiosaurus transylvanicus, as well as various small theropods. Besides dinosaurs, there are crocodilians (Allodaposuchus and Doratodon), turtles, and lizards. Fishes, amphibians, birds, and multituberculate mammals are other vertebrates making up this assemblage. More often than not, the remains are fragmentary, scattered and weathered, except for those preserved within sediments of lacustrine origin.
The Transylvanian Basin is surrounded by the Apuseni Mountains, the Eastern Carpathians and Southern Carpathians. It has a roughly circular shape with Upper Cretaceous to Upper Miocene sedimentary fill reaching in some place up to 8 km in thickness. It is a post-tectonic basin and represents a typical back-arc basin starting to the Upper Miocene. Geological and geophysical data show that the sedimentary cover of the Transylvanian Basin has formed during at least seven sedimentary cycles: Permian – Triassic, Jurassic – Lower Cretaceous, Upper Cretaceous, Paleogene, Lower Miocene, Middle – Upper Miocene and Pliocene. Structural elements of the Transylvanian basin basement belong to the Inner Dacides, Transylvanides and Median Dacides resulted from subduction and collision processes, especially collision between the Foreapulian block and Getic block during to the Austrian tectonic phase (Albian Collision) and pre-Gossau phase. These compressional tectonic phases have generated in the Transylvanian Basin the north-south overthrust lineaments with an eastward vergence by extensional reactivation of old structures from Middle Triassic-Lower Cretaceous (normal system faults generated by the Thetysian spreading processes). Later, the Carpathian tectonic phases (Laramian, Old Styrian, New Styrian, Moldavian and Wallachian Phase), recorded, especially, in the Eastern Carpathians through the emplacement of the other Carpathian nappes (Outer Dacides, Moldavides) contributed to the thrust reactivation, some with the appearance of the new structural elements, northwards tilting of the pre-Miocene basement, basin subsidence, uplift and erosions in the Transylvania Basin.
An example on this way is the system of Cenade-Ruşi-Veseud reverse faults, which is a result of the Wallachian tectonic phase (Pliocene/Quaternary). The Middle Badenian Salt Formation overlies the Cenade-Rusi uplift and this uplifting was generated by the thrust Laramian tectonic phase. The system of Cenade-Ruşi-Veseud reverse faults was activated at the beginning of the Pliocene and it was ruled by a combined tectonokinetic-halokinetic mechanism. The structural map with isochronous (TWT) of the top of Salt Formation shows that fault has a sinuous trend with three segments: the Cenade is on N–S direction, the Ruşi segment becomes NW-SE orientated, and the last segment, the Veseud has a WNW-ESE trending with eastward vergence and affect sedimentary deposits, including Pliocene deposits. Along this system, the Badenian Salt Formation has a column diapiric shape. Due to the very high uplift of Eastern Carpathians which occurred in the Late Miocene-Pliocene (about 4 km uplift and continues to the present day) and higher Upper Badenian-Pliocene sedimentation rates (recorded in the Eastern and Central parts of basin) combined with the Pliocene- Quaternary uplift of the Apuseni Mountains and the presence of the some strike-slip faults developed a pushing pressure of the Salt Formation toward the center and southwestern parts (salt sliding) of basin with the initiation of these reverse faults. Coevally with the Pliocene uplift of the South Carpathians (considerate as rigid fix block for the Miocene-Pliocene sediments of the Transylvanian Basin - after this uplift) were developed normal faults in the southern part of this basin, parallel to the orogen and evolution of the Cenade-Ruşi-Veseud reverse system faults don't stop, it is still activate.
Earthquake forecasts have always been a difficult task because they can be affected by uncertainty in terms of the most appropriate model and the involved parameter values. The application of two quite different models to the same seismogenic area was explored. The first belongs to the category of the renewal models, based on the characteristic earthquake hypothesis, the necessary ingredients of which being historical or paleoseismic recurrence times, and a fixed geometry for the faults. The hazard rate so obtained is then modified by the inclusion of a permanent effect due to the Coulomb static stress change caused by failure of neighbouring faults that occurred since the latest characteristic earthquake on the concerned fault. The second model consists of a very simple earthquake simulator, which can be described by parameters taken from two data input classes, fault slip rates and adoption of a Gutenberg–Richter magnitude–frequency distribution. This information is commonly available even if historical and paleoseismic recurrence data are lacking. The intention is to develop and assess a simulator that has a very limited parameter set, which has the benefit ofreducing and quantifying uncertainty. We apply both methods along the Corinth gulf extension zone, a place that is rich with observations of strong–earthquake recurrence behaviour, to assess their relative forecast applicability. We find that use of slip rate as a primary constraint allows the simulator to replicate the pattern of observed segmented rupture rates along the Corinth seismogenic zones. As they evolve through time, our rupture simulations preferentially fill slip gaps, enabling estimates of time–dependent segment recurrence. We conclude that very simple earthquake rupture simulations based on empirical data and fundamental earthquake laws can be useful forecast tools.
Submarine hydrothermal mineralization occurs in at least five locations in the South Aegean (Hellenic) Volcanic Arc; from west to east of Methana, Milos, Santorini, Kos and Nisseros/Yali. Manganese and iron enrichments in seawater and marine sediments are sensitive indicators of the presence of this hydrothermal activity and are sometimes the only obvious indication of it. Comparison of the Mn and Fe contents of hydrothermal waters from the five locations listed above show that those from the inner parts of the hydrothermal embayments of Santorini are more enriched in Mn and Fe than are those from almost all of the other hydrothermal locations studied, more than 400 ug/l Mn and 5000 ug/l Fe. Hydrothermal waters from the Santorini outer exhalative zone are much depleted in Mn and Fe (17 & 149 ug/l respectively) and fall within the range of values in hydrothermal waters found of Yali (4.5-28 ug/l Mn & 9-221ug/l Fe). Kephalos Bay, Kos contains hydrothermal waters averaging only 14 ug/l Fe while Mn there was beneath detection (0.5 ug/l). Milos offshore hydrothermal waters range from 21-522 ug/l Mn and 35-322 ug/l Fe, more similar to each other than at all of the other locations except Methana. Hydrothermal waters in Thiafi Bay, Methana, contain a relatively low 1-12 ug/l Mn & 7.5-24.4 ug/l Fe. Fe/Mn ratios also vary in hydrothermal waters along the arc. Those from Santorini vary between 11 & 16 in the inner exhalative zones of the embayments, 8.7 in the outer exhalative zones (probably reflecting the selective precipitation of Fe over Mn with increasing distance from the vents), and 2.5 in the caldera. Off Yali, Fe/Mn ratios vary from 6-13. By contrast, of Milos and Methana they are much lower, varying from only 0.37 to 1.66 at the former and 2.4 at the latter. Clearly therefore, Mn is enriched relative to Fe in the hydrothermal waters of Milos and Methana compared with other hydrothermal locations along the arc. There are variable hydrothermal enrichments of other elements such as Zn, Cu and As along the arc too, highest of Santorini. Thus it appears to be an increase in hydrothermal inputs in waters from the ends of the arc towards the centre. Along arc comparisons of the composition of metalliferous sediments from near the hydrothermal vents is complicated by their variable detrital and volcaniclastic content. In order to eliminate this, all comparisons below are made on the basis of analysis of the sediment fine fraction in which the hydrothermal precipitates are concentrated. The greatest concentrations of Fe and Mn oxides in sediments along the arc occur at Santorini, where Fe/Mn ratios decrease away from the vents due to the selective precipitation of Fe relative to Mn. Lesser enrichments in both elements occur off Yali where the average Fe/Mn ratio falls within the range of that between the Santorini inner and outer exhalative zones. At Kos, Fe is less and Mn more than at Yali,while at Milos Fe is less and Mn mostly close to(with the exception of Mn in the Voudia Bay sediments) their Aegean Sea sediment average. This could be due both to the sub-surface precipitation of hydrothermal minerals and to the metal rich hydrothermal waters that emerge on the seafloor being dispersed over a wider area at Milos than at either Santorini and Yali due to the more topographically restricted settings of the latter relative to that of the former. Fe/Mn ratios in sediments of Milos are amongst the lowest encountered in the South Aegean Volcanic Arc, except at Voudia Bay, where the ratio is elevated principally due to very low Mn there. In Thiafi Bay, Methana, Mn varies from 578-1360 ppm and Fe from 5-8.6%. The former values are similar to those found in the Santorini exhalative zones and some locations at Milos, and the latter are between those occurring at Milos and Yali. There appears, therefore, to be no clear increase in Fe and Mn values in sediments from the ends of the arc towards its centre, although they are highest at Santorini. Much of the variation in the Fe/Mn ratio in the sediment fine fraction between the different hydrothermal locations along the arc can probably be attributed to where the waters from which the oxides precipitate lie in the Fe-Mn hydrothermal fractionation sequence. As far as the writers are aware, ancient hydrothermal mineral deposits have only been described from two of the South Aegean Volcanic Arc islands, Milos and Santorini. At Milos, there are several hydrothermal mineral deposits including the Vani manganese deposit. Santorini has a much more limited known fossil hydrothermal mineral assemblage, consisting of iron oxides and other minerals impregnating basement rocks in bands up to several cm thick at the base of the caldera wall near Thermia. The enrichment of Fe in the Santorini waters and sediments would be in keeping with the only known fossil hydrothermal mineral deposits there also being iron rich, suggesting that the Santorini hydrothermal system may be richer in Fe than those of the other islands. The large variability in the composition of the ancient hydrothermal deposits on Milos precludes detailed comparison with the hydrothermal waters and sediments there at the present time, but is a worthwhile subject for future research.
According to the extrusion or escape model the Pelso tectonic unit should be palaeogeographically situated before Palaeogene and Early Neogene tectonic processes between the Eastern and Southern Alps (SA). In this long known palaeogeographic reconstruction the Early Cretaceous sequence of the south-western part of the Transdanubian Range (TR) (South Bakony and Zala Basin) should resemble the Maiolica/Biancone facies successions of the SA. In contrast the Early Cretaceous of the Gerecse Mts. should correspond to the Rossfeld sequence in the Salzburg Northern Calcareous Alps (NCA). It is not so well known that there are also significant facies differences between the south-western and the north-eastern segments of the TR and that these differences also correspond to those of the SA and the NCA. The basal Jurassic of the SA developed in huge areas on top of shallow-water carbonates, which were deposited in direct continuation of the Late Triassic platform in varied tectonic subunits: Friuli Limestone (Calcari grigi del Friuli), Misone Limestone (Calcari grigi), or San Vigilio Limestone (Calcare oolitico di San Vigilio). These formations correspond to the Kardosrét Lst. in the Bakony; in contrast this facies is missing in the NCA and also in the Gerecse Mts. One of the most typical facies of the Jurassic is the ammonite-bearing, red, nodular, clayey limestone (“ammonitico rosso”) both in the SA and the Bakony. It is called Tűzkövesárok Fm in the Early Jurassic, Tölgyhát Fm in the Middle Jurassic and Pálihálás Fm in the Late Jurassic in Hungary. A more deep-water formation is the radiolaritic Selcifero Fm in the Lombardy and the Lókút Radiolarite (Bakony Mts.) in the late Middle Jurassic to Oxfordian. The larger part of the Late Jurassic and the Early Cretaceous in the Lombardian Basin is represented by the Maiolica facies, while it is only developed in the Tithonian to Hauterivian and pinches out eastward in the Southern Bakony. Jurassic successions of the Gerecse Mts. show similarities to those known from the Tirolic units of the NCA. The base of the Jurassic in the Gerecse is represented by the Pisznice Lst., equivalent to the condensed red limestones of the Adnet Group of the NCA. Both of them cover the surface of the Dachstein Fm. with gentle angular unconformities. Sedimentation on submarine highs is characterized by condensed red limestones; in contrast in the basinal areas grey cherty limestones were deposited. On the Middle Jurassic highs, the red, nodular limestone is called Klaus Fm. in the NCA and Tölgyhát Lst. in the Gerecse. It is followed by the Ruhpolding Radiolarite in the NCA and Lókút Radiolarite in the Gerecse. In the Tirolic units of the NCA the radiolarite succession contain several olistromatic breccias, partly of exotic and partly of local provenance (Hallstatt and Tauglboden Mélanges). The Lókút radiolarite of the TR is followed by or include a breccia bed called „Oxfordian breccia”, which may correlate with the Tauglboden Breccias. The Agatha Fm. of the NCA mirrors the Pálihálás Limestone of Kimmeridgean–Early Tithonian age in the Gerecse, while the Oberalm Fm. matches the Szentivánhegy Lst. of the Tithonian-Berriasian. In the Early Cretaceous the carbonate succession is replaced by turbiditic siliciclastics (Bersek Marl Fm. in the Gerecse and Schrambach Fm. in the NCA). The sedimentation changed from carbonate into siliciclastics diachronously and the time equivalent Felsővadács Breccia Mb as a massflow deposit cuts this boundary in the Gerecse. This breccia is thicker and wider spread in the NCA and called Barmstein Breccia. This body is replaced by the lowermost coarse-grained turbidites of the lowermost Rossfeld evolution. Upsection the Bersek Marl is followed by the Lábatlan Sst in the Gerecse and the lower part of the Rossfeld Fm. by the upper one in the NCA In both regions the Rossfeld coarsening-upward cycle was interpreted as expression of nappe thrusting, whereas for the NCA nowadays for the Rossfeld Basin fill a foreland-basin character (Molasse sediments) is favoured.
Conclusion: The TR is a special tectonic unit showing in part homogeneity to the SA (Bakony) and in part to the NCA (Gerecse). So its original palaeogeographic position has been situated between the NCA and the SA.
The main aim of the WG project is to identify and correlate lithostratigraphic units developed within the CBGA region. Although there are some lithostratigrahic units the names of which are used internationally within the region, the overwhelming majority of the units has special names from country to country in spite of the fact that many of the units are crossing one or several country borders. Therefore we want to identify and correlate major lithostratigraphic units in order to exclude unnecessary repetitions of names for well identifiable lithostratigraphic units. Calculating just 400 Mesozoic lithostratigarphic units by countries, in the CBGA region altogether there can be around 5000 units from which let us say 10% are common at least in two countries. This way the great amount of names could be decreased by 500. Supposing there are several units crossing 3-5 or even more country borders the number of lithostratigraphic units could be diminished by another 500.
What is the advantage of decreasing the numbers of names? It can promote a better understanding of the geological and geotectonic setting and via this the geological history of certain areas or broaden the frame of the known areas. Correlation of unified units from one segment of the Alpine orogen to the other will help in further understanding of the Tethyan closure and the Alpine mountain building. Besides that, how great advantage would it be for students if they could operate with fewer numbers of names.
Difficulties may arise while trying to correlate and unify lithostratigraphic units from country to country. We know that there aren’t any formations with 100% identity; if we succeeded in correlating a few formations we shall select a common name from among those names used so far in one of the countries for the future to be accepted by the national committees. We shall agree in regulations in advance to follow it in those cases where the solution is not obvious for everybody. There can be several stand points such as: which name was given first; which formation was described most properly; which formation's stratotype is better and more easily accessible; which name can be written and pronounced more easily, etc.
Because of the great number of lithostratigraphic units, and in order to promote the successful correlation the WG is subdivided into sub-WGs: Triassic Sub-WG, Jurassic Sub- WG and Cretaceous Sub-WG.
The introductory talk wants to give general information about the aims and structure of the project, about the approach and steps to be used during the process and also wishes to introduce proper situation when the correlation was successful without forcing it.
In the Western Pannonian Basin the widespread occurrence of ventifacts and large scale deflation features – like a system of yardangs, deflation hollows and basaltic buttes at least in part exposed by wind erosion – indicate strong wind activity during the Quaternary. This is supported by common presence of wind-blown sediments, like loess and aeolian sand. The Pleistocene glaciations are probably the most important periods of deflation, when the Pannonian Basin was a dry, periglacial area with scarce vegetation and strong winds. However, age of the wind-polished rock surfaces exposed on different geomorphic horizons of the Transdanubian Range – an uplifted low elevation (up to 750 m asl.) range in the Western Pannonian Basin – has remained unknown so far, although they can provide time constraints of landscape evolution. We used in situ produced cosmogenic 10Be to determine exposure time and denudation rate of wind-polished rock surfaces and regional (basin) scale denudation rates are also inferred. In view of surface samples only, minimum exposure ages assuming no denudation are ranging from 0.09 to 1.3 My with most of the ages between 100 and 400 ky. Considering the maximum denudation rates assuming that steady state is reached, yield to rates ranging from 0.36 to 8.42 m/My. In both assumptions, allowing for all surface samples, there is a weak, maybe apparent correlation between age and/or denudation rates versus altitude; saying that the higher is older and/or more resistant. Allowing for the maximum denudation rates of samples from the depth profiles one can observe that for the uppermost samples these rates are the same within uncertainties. This evidences the fact that steady state has been reached. However, for deepest samples, denudation rates become higher. This thus implies that steady state has not been reached at those depths. Accordingly, depth profiles allow determining simultaneously both denudation rate and exposure age. Measurements of 10Be concentrations along depth profiles of exposed, ventifacted rocks allow to derive a local denudation rate of 3.46-3.88 m/My and exposure ages as old as 1.5 My. Regional denudation, which occurred mainly via deflation of the loose sediments, varies between 40 and 80 m/My. Our results show that aeolian erosion in continental, periglacial areas of Central Europe played an important role in Quaternary landscape modification. Besides, the newly determined exposure ages are strong time constraints on the onset of denudation, exhumation of the Transdanubian Range, which is indicative of the minimum time of the uplift of the range.
An analysis of the operational “Hail Suppression Project” in Serbia that used silver iodide dispensed from anti-hail rockets was performed for the period 1981-1986 in order to estimate the seeding agent amount reaching the surface of the target area in precipitation. The primary aim of our investigation is to estimate whether amounts of silver iodide exceeds the threshold of 1 μg/m2 from one seeding event, which in turn, may be of importance for an analysis of apparent afterseeding effects and environmental pollution. This period is selected due to the largest amounts of the seeding amount performed (the maximum is over 103 kg per a season, 4.4 tones per a six-year period). Our analysis is performed for areas monitored by S band radars located near Valjevo and Užice. The radar observations give us the possibility to estimate the precipitation area associated with a seeded hail cell. It is well known that this area is often much smaller than the analyzed target area independently of a storm type. Our method is based on the next assumptions: each seeding operation was performed according to the seeding criterion; both activated and non activated agent particles reach the ground; analyzed precipitation area is associated only with a single hail cell which satisfies the seeding criterion; the hailstorm precipitation efficiency is 60%; the agent particles are uniformly distributed within the accumulated precipitation area at the surface. In such way, we performed estimates of the seeding agent amount reaching the ground after seeding.
We analyzed the seeded hailstorms tracking over analyzed area from NE, SE, SW and NW direction associated with the frontal passage and individual ones. The individual hail clouds from the north-western direction require the special treatment due to the formation of the hailstreaks along the major axis of the Western Morava valley. A hailstreak has the surface ranged in the interval between 100 and 500 km2. For each storm passage, they are observed at the approximately same locations. As expected, the tracks of the hailstorms associated with the frontal passage do not show regular spatial pattern. On the other hand, they are correlated with larger amounts of convective precipitation and silver iodide particles at the ground. Our calculations show that the amounts of the silver iodide at the ground in average are below the threshold in many cases. Our analysis, however, shows that these amounts may exceed the lower boundary more times for some frontal passages and over a single hailstreak associated with an individual hailstorm. In this occasion we must emphasize an important fact. The silver iodide amounts at the ground are underestimated due to the reason that the silver iodide particles are not uniformly distributed in the accumulated precipitation area as well as they do not fall down suddenly via precipitation after seeding starts.
Our preliminary results give the basis for further investigation of such a kind. In the next period, the total loss of the seeding material in the operational “Hail Suppression Project” was smaller. But, this does not mean that the critical threshold of silver iodide amount did not attain in some areas after one seeding event. This requires further detailed investigation for the whole target area and longer time period following the proposed method. The estimation of seeding agent amounts per seeding event only on the basis of total agent loss, the number of seeding events and for the whole target area is wrong for the reason of great underestimation of real seeding effects. Seeding scenarios with considerable amounts of the silver iodide at the ground after seeding are the warnings for ecologists to organize different observations after seeding events with extreme agent loss as well as for various microbiological observations associated with persistent effects of cloud seeding. We believe that the amounts of silver iodide may be decreased by the improvement of hail suppression methodology based on additional investigations.
Hail causes considerably damage to crops and property. In many areas of the world the cloud seeding with the goal of suppressing hail is common practice. The seeding agent is injected into the target cloud from aircraft, ground-based generators or the agent is injected into the cold peripheral parts of a cloud by rockets. The success of hail suppression activity is influenced by careful selection of seeding time, seeding dynamics, seeding agent amount and location of initial seeding zone. In the last decade, the cloud-resolving mesoscale models become widely used in testing the seeding criterions with respect to above parameters. The
simulation of seeding effects can be done by either explicit microphysics or bulk microphysics schemes. Bulk microphysics scheme is frequently used in the cloud-resolving mesoscale models due to lower computational cost. This scheme assumes a distribution function for the cloud and precipitation size particles. The variation in accumulated convective precipitation due to the uncertainties inherent in the selection of distribution functions and their parameters must be assessed. Until now the cloud-resolving mesoscale models are used in some studies that quantify considerable sensitivity of the amount of accumulated precipitation from a hailstorm on variations of cloud drop size distribution. Main consequence of the hail suppression activity is the accumulated convective precipitationchange. The selection of cloud drop size distribution is therefore critical for an adequatetreatment of seeding effects.
We use the numerical model of cloud with two microphysical schemes involving the unified Khrgian-Mazin size distribution of cloud drops and a scheme involving monodisperse cloud droplet spectrum and the Marshall-Palmer size distribution for raindrops, respectively. The unified Khrgian-Mazin size distribution approximates the entire drop spectrum that splits into cloud droplets and raindrops at diameter of 100 μm. This drop size distribution is a function of two parameters: total liquid water mixing ratio and mean cloud drop spectrum radius. Sensitivity tests with respect to the amounts of seeding agent, location, time and dynamics of seeding are performed in order to investigate accumulated precipitation change in comparison with an unseeded case using both microphysical schemes. Silver-iodide agent is used in all experiments. Three mean cloud drop radii of 10, 30 and 50 μm are used in sensitivity tests with the unified Khrgian-Mazin size distribution.
Our principal findings are as follows:
For an unseeded hail cloud, the unified Khrgian-Mazin size distribution with a mean cloud drop spectrum radius of 10 μm leads to the huge increase of accumulated rain precipitation (up to 275%) and decrease in hail precipitation (-71%) compared to the counterpart with the Marshall-Palmer size distribution of raindrops and the monodisperse cloud droplet spectrum. Comparison of seeded cases with an unseeded one show the maximum increase of rain precipitation (13.7%) and decrease of hail precipitation (50.2%) if the Khrgian-Mazin size distribution is used. In general, this precipitation changes are greater than those simulated using the alternative approach. Analysis of above results leads to the conclusion that the radar reflectivity criterion alone is insufficient for decision making about hail suppression. The drop spectrum must be also known just before the agent injection due to the optimal seeding agent consumption.
Peraluminous granites are often found in collision-related geotectonic frameworks and usually were attributed to various crustal melting. Their composition proved to be very important as an indicator of particular conditions or specific tectonic phases in the frame of the existence of an orogen. The tectonic framework of the southern margin of the Pannonian realm and northern Dinarides was finally established during the Miocene. In this area, fingerprints of transitional tectonics, from the Oligocene post-collision, which dominated in the Dinarides, to the
Miocene extension, occurring predominantly within the Pannonian/Intra-Carpathian area, may be reconciled.
In this context, granitoid rocks of Mt. Bukulja show characteristics that should be linked to specific geodynamics: (1) it is situated at the very southern margin of the Pannonian Basin, (2) it is characterized by Neogene peraluminous granitic rocks, and (3) it shows Nb- Ta-Sn metalogenetic features. Therewith, they differ from the widespread plutono-volcanoplutonic provinces in Serbia, which are dominated by Late Oligocene, mostly calc-alkaline igneous rocks related to Pb/Zn±Ag±Sb metallogeny.
The granitic mass of Mt. Bukulja crops out about 60 km southern of Belgrade as an EW laccolite-shaped igneous body covering an area of about 40 km2. It is concordantly intruded into low-grade metamorphosed Devonian/Carboniferous schists in the West and into Cretaceous sandy marbles, clay sandstones and limestones in the East.
The bulk of the granitoid mass is represented by medium-grained to slightly porphyritic, slightly peraluminous two-mica granite (TMG). Metaluminous hornblende-biotite and biotite-bearing (H-BG) granite and rare aplitic granite are subordinate, and the former occur as patches or enclaves of various dimensions (from several decimeters to several tens of meters) or as isolated outcrops within deep creeks. The available radiometric age suggests that TMG was emplaced around 20 Ma whereas the age of H-BG is inadequately constrained. A lamprophyre dyke (BLD) similar in composition and age to other Serbian primitive minettes with a K/Ar age of 26 Ma has been found in the vicinity of Mt. Bukulja. TMG and H-BG show similar petrographic characteristics but the evidence of magma interaction processes are found only in H-BG. In comparison to H-BG, TMG are less enriched in most trace elements including REE and have a more fractionated REE-pattern and higher Euanomaly. TMG display a wider range of initial Sr-Nd isotope ratios normalized on 20 Ma (87Sr/86Sri=0.70652-0.71368 and 143Nd/144Ndi=0.51223-0.51283) than do H-BG (87Sr/86Sri=0.70768-0.70781 and 143Nd/144Ndi=0.51242-0.51256). Geochemical modelling suggests that H-BG could have derived from a BLD-like melt by mixing plus fractionation processes assuming a batch of TMG-like magma as the acid end-member. On the other hand, the geochemical variability of TMG is reproduced by an AFC model with assimilation/fractionation ratio r=0.5 and with high amount of crustal component (~20-50 %) starting from the least evolved TMG rocks. In the modelling, the average composition of the least evolved TMG samples were used to represent parental magma composition whereas the composition of adjacent metamorphic rocks was adopted as possible contaminant. The composition of the least evolved TMG implies that TMG parental magma likely originated by melting of a mafic lithology such as earlier basalts underplating in the lower crust. The high proportions of assimilation along with other geochemical and geological evidence suggest that the Mt. Bukulja TMG originated within the same geotectonic setting as acid volcanics of the north Pannonian Basin. The results of this study support the hypothesis that the Mt. Bukulja pluton is related to tectonomagmatic events controlled by the early extensional phases in the opening of the Pannonian basin.
Methane soil flux measurements have been made in 38 sites at the geothermal system of Sousaki (Greece) with the closed chamber method. Fluxes range from –47.6 to 29,150 mg m-2 d-1 and the diffuse CH4 output of the system has been estimated in 19 t/a. Contemporaneous CO2 flux measurements showed a fair positive correlation between CO2 and CH4 fluxes but the flux ratio evidenced methanotrophic activity within the soil. Laboratory CH4 consumption experiments confirmed the presence of methanotrophic microorganisms in soil samples collected at Sousaki. These results further confirm recent studies on other geothermal systems that revealed the existence of thermophilic and acidophilic bacteria exerting methanotrophic activity also in hot and acid soils thereby reducing methane emissions to the atmosphere.
The Thrace Basin (Turkey and Greece) is located between the Rhodope-Strandja Massif to the northwest, the Marmara Sea and Biga Peninsula to the south and the Black Sea to the east. It consists of a complex system of depocenters and uplifts with very articulate paleotopography indicated by abrupt lateral facies variations. Most of the basin fill ranges from the Eocene to the Late Oligocene and consists mainly of turbiditic deposits with a significant volcaniclastic component, evolving upwards to shelf and continental deposits.
Sediment source areas and paleodispersal pattern of the southern Thrace Basin were determined by studying framework and heavy-mineral compositions of arenite samples (78 samples for framework composition and 40 samples for heavy minerals). Samples were collected at six localities, which are from west to east: Gökçeada, Gallipoli and South-Ganos (south of Ganos Fault), Alexandroupolis, Korudağ and North-Ganos (north of Ganos Fault). The Thrace Basin fill is made mainly of lithic arkoses and arkosic litharenites with variable amount of low-grade metamorphic lithics (also ophiolitic), neovolcanic lithics, and carbonate grains (mainly extrabasinal). Picotite is the most widespread heavy mineral in all petrofacies.
The average values and distribution of several petrographic parameters discriminate six petrofacies. These parameters are: Q+F/NCE+CE (occurrence of granitic rocks in source area), OF/L (total of ophiolitic rock fragments), F+S/L (amount of metamorphic lithics), CE/L (quantity of carbonate extrabasinal grains), NEOV/NCE (presence of neovolcanic component, both single grains and lithics), CI/L (total carbonate intrabasinal grains), and the amount of the four principal heavy minerals (picotite, sphene, glaucophane and epidote groups).
Integration of the petrographic dataset (gross and heavy mineral composition) with stratigraphic analyses and paleocurrent measurements points to a complex sediment dispersal pattern in the southern Thrace Basin during Eocene-Oligocene times. The main sediment source area was located to the south, including the region of the İzmir-Ankara suture and another poorly dated suture located in the Biga Peninsula. Detrital input from this source area is characterized by the abundance of picotite and ophiolites with low-grade metamorphic rock fragments and extrabasinal carbonate grains. A possible secondary source area is represented by the Rhodope Massif to the west. Detritus possibly derived from this area is characterized by picotite with plutonic and metamorphic rocks. Such Rhodopian provenance, although quantitatively subordinate in the study area, seems to have played a significant role in providing detritus to the central and northern sectors of the basin. An important penecontemporaneous volcanic component is widespread in late Eocene-Oligocene times, indicating widespread post-collisional (collapse?) volcanism following the closure of the Vardar-Izmir-Ankara ocean.
In summary, the most important source area for the sediment of Thrace Basin in the study area was represented by the exhumed subduction-accretion complex along the southern margin of the basin (Biga Peninsula and western-central Marmara Sea region). Most measured paleocurrent indicators show an eastward paleoflow but this is most likely the result of gravity flow deflection. This is possible considering the strong control of the east-westtrending synsedimentary transcurrent faults which cut the Thrace Basin, generating a series of depocenters and uplifts, which deeply influenced sediment dispersal and the areal distribution of paleoenvironments.
A good understanding of the age and geodynamic evolution of ophiolite complexes is of key significance for the reconstruction of the past oceans. Since most extrusive events (i.e. lava flows) are often covered or intercalated with pelagic siliceous sediments, their dating provides a relatively detailed time frame to describe the magmatic events that took place in parts of the Tethyan oceanic realm. Radiolaria are often the only fossils preserved in these sediments. Therefore, Radiolarian biochronology has become an important tool to investigate the complex geodynamic evolution of Alpine mountain belts.
The main aim of our project is to specify the geohistory of ophiolites preserved in the Lesser Caucasus, a key area of the Alpine-Himalayan mountain belt. Improved knowledge on this subject will allow better lateral correlations of possibly equivalent suture zones and will help deciphering the geodynamic evolution of the greater area between Eurasia and the South-Armenian Block. The latter was a micro-continent that has become detached from Gondwana during the Late Palaeozoic – Early Mesozoic. It is considered as a part of the eastward extension of Taurides-Anatolides continental microplate.
Two main ophiolitic zones are recognised in the Lesser Caucasus:
- The Amassia-Sevan-Akera ophiolites (running from NW Armenia, through East of Lake Sevan to western Karabakh) represent the main suture zone in the Lesser Caucasus, including extensive outcrops of peridotites (often serpentinized) and gabbros. The geochemistry of lavas suggests the presence of two distinct extrusive systems; i) a contaminated MORB series of basalts, bearing a slight calc-alkaline signature, is considered to be the result of a slow spreading ridge in a back-arc setting; ii) an alkaline OIB series of lavas considered to be the expression of a mantle plume event.
- The Vedi ophiolite, in the SE of Yerevan, is also composed of serpentinites, gabbros and a thick pile of massive and pillowed lava flows. It is considered as a folded klippe sequence that was thrusted over Cenomanian-Turonian shallow water carbonates and flysch of the South Armenian Block.
New and revised radiolarian data point to the following working scenario:
(1) the initial phase of sea floor spreading took place during the Late Triassic (Carnian). Evidence for this comes from a single locality.
(2) The bulk of oceanic crust, preserved today in both the Sevan-Akera and Vedi ophiolite complexes, was formed during the Middle Jurassic (Bajocian, Bathonian-Callovian) in a supra-subduction zone (SSZ) setting;
(3) Submarine volcanic activity continued occasionally during the Late Jurassic and Early Cretaceous, as this is suggested by reliable radiolarian ages obtained on cherts intercalated with tholeitic lavas from both the Vedi and Sevan ophiolites.
(4) Preliminary results on radiolarian cherts intercalated with alkaline lavas of the Sevan ophiolite suggest that a hot spot event took place during the Late Jurassic.
(5) Several tuffite levels, intercalated within the radiolarite sequence of the Sevan ophiolite, reflect a Late Jurassic subaerial volcanic. At the moment, it is unclear whether they are related with the emplacement of the SSZ ophiolites or with the mantle plume event.
We present an overview of the well developed and commonly followed standard methodologies in underwater archaeological research along with recent technological progress in deep water surveys. Our aim is to identify challenges posed by the state of the art marine engineering achievements and to explore perspectives towards an interdisciplinary methodology and concept for the benefit of underwater archaeological research and in the frame of the archaeological deontology.
Remote sensing marine geological-geophysical techniques enable quite high resolution mapping of the seafloor at almost any depth. Underwater vehicles, manned or unmanned, autonomous or remotely operated, equipped with highly sophisticated scientific devices extend the limits of underwater archaeology to include almost full ocean depths.
Mutual understanding and close collaboration between archaeologists, marine scientists and engineers is a prerequisite for the best use of technology and experiences for the benefit of deep water archaeology.
The tectonic structure of Lesvos is characterized mainly by an extensional regime acting from Neogene to recent while it is also under the influence of the westward migration of the southern branches of the North Anatolian Fault and the North Aegean Trench (NAT). Some of the main active faults of Lesvos Island are extended along the Geras gulf, which form an area of particular importance due to its proximity to the town of Mytilene. At a primal study of faults, a rift zone was found by neotectonic mapping, with deep-slip to oblique-slip normal faults of general direction NW - SE and W – E, respectively. Afterwards, based on rural measurements, the stress pattern of the area was studied as the main directions of the strain-stress field trends (σ1, σ2, σ3) were calculated. In some specific sites of fault surfaces overlapping generations of slickenside striae were observed, meaning that more than one field tectonic trends acted in the same position in different time periods. The results include two main distinct tectonic phases; the oldest one with extensional axis directed NESW and the newest trending NNW - SSE. The tectonic analysis and the interpretation of digital relief model (DEM), as well as the use of satellite imagery of the study area, have contributed significantly to the quantitative and qualitative analysis of morphotectonic characteristics of the faults. On the basis of the digital relief model, morphological sections were constructed perpendicular to the faults in order to extract information on the morphology of the slope. Moreover, profiles of morphological slope gradients were constructed along faults, based on the slip map of the digital relief model, with mean gradient ranging from 14° to 16° for most of the faults. These values seem to be related to the lithology of the rising block and the uplift rate. Shaded relief maps and three-dimensional imaging helped identifying faults. The determination of the effect of the tectonic geomorphological phenomena can be defined and quantified with morphotectonics indicators. In the present study five (5) morphotectonics indicators were applied: Stream Length – Gradient Index (SL), Drainage Basin Asymmetry Factor (AF), Hypsometric Integral (HI), Ratio of Valley – Floor Width to Valley Height (Vf), Mountain – front Sinuosity (S). The calculation of morphotectonic indicators in the regional faults confirmed the activity, and the recent action, which gave rise to the tectonic structures observed today. The high values of the SL index are found in morphological slope of the faults. The AF index shows a river spin, possibly due to the influence of faults, which either lift or humiliate the respective pieces of the rift zone. The index Vf exhibits relatively low values indicating a strong, deep erosion of the streams rising in the piece. The estimates of Mountain – front Sinuosity index are ranging from 1.1 to 1.6
and characterize active faults, though not associated with any known historical earthquake. Finally using empirical magnitude - fault length relationships, for the Gera’s Gulf area, the maximum expected magnitude earthquake for each fault or fault zone is calculated to Ms = 5.7 – 6.3.
The studied area is located in the western part of the Tauride carbonate axis forming a north pointing cusp, so-called Isparta Angle, in SW Turkey. Autochthonous carbonates and flysch type sedimentary rocks form the basement of the area and are tectonically overlain by ophiolitic melange of the Lycian nappes. All these units are cut in some places by the Plio-Quaternary Gölcük volcanics and covered by Quaternary pyroclastic tuffs and alluvial deposits. Additionally, the rest of Isparta area is made up of sedimentary rocks (Jurassic to Oligocene) and Pliocene-Quaternary (6.75 Ma-24,000 year) volcanic rocks. Hydrogeologically, the rocks in the area are classified as permeable, semipermeable, slightly permeable, and impermeable. Among these hydrogeological units, the alluvium, volcanic tuffs, and limestones are considered as aquifers in the area. The groundwater flow direction in the Isparta plain is generally from SW to NE comparable with the gently slope of pyroclastic fall deposits extending from Gölcük caldera in the SW to province capital of Isparta.
The water is one of the most important basic resources for the human life. The drinking water must be of drinkable quality corresponding to drinking water standards. Therefore, the quality control of drinking water is very important. In this study, to determine the distribution of water in drinking water system, 46 samples were collected from town of Isparta and its surroundings accompanying with the in situ measurements of temperature, pH, electrical conductivity, total dissolved solids, redox potential, dissolved oxygen, alkalinity and acidity tests. 46 water samples have been analysed for their anions, cations and some trace element contents by Inductively Coupled Plasma Optical Emission Spectromety (ICP-OES) and Ion Chromatography (IC). It was concluded that the results are comparable with national (Turkish Standards Institution – TS 266 2005) and international (World Health Organisation – WHO 2006, United States-Environmental Protection Agency – US EPA 2002 and European Union – EU 1998) drinking water standards. The waters in the studied area can be considered as Ca-Mg-HCO3 and Ca-HCO3 type exchange-waters. Until 1995, the drinking water for the people from the capital of Isparta have been supplied by water springs of Andık and Gölcük lake. Since 1995 due to increasing water requirements, drinking water system are ensured by Eğirdir lake waters. The results of hydrogechemical analyses show that the Eğirdir Lake water dominates in drinking water system of Isparta. Nowadays, the high fluoride contents in drinking waters from Isparta and its surroundings are reduced by mixing process with the waters of Eğirdir Lake which reach sometimes standard fluoride values and lie under standard fluorine values (<0.5 mg/l). F-contents in waters below the standard value (<0.5 mg/l) may give rise to dental and medicine problems. Therefore, mixing operations for the drinking waters used in town of Isparta must be carried out very carefully.
The studied Pb-Zn-Cu deposits are located between Çanakkale and Balıkesir provinces in NW Anatolia. Two deposits are investigated in these provinces, Lapseki-Çataltepe and Yenice-Kalkım deposits, situated to the northwest and southeast of Çanakkale, respectively. The main rock units in the region range in age from Paleozoic to Tertiary. Paleozoic rocks are generally characterized by Karakaya Complex units which are represented by Permo-Triassic metamorphic rocks consisting of schists and calcschists with lens- and/or band-shaped recrystallized limestones and/or marble intercalations. Tertiary rock units are represented by Eocene granitoids and volcanics in Lapseki area, and Oligo-Miocene granitoids and Middle Miocene volcanic rocks in the Yenice area. Mineralized zones in both deposits occur as hydrothermal veins in carbonate levels of metamorphic rocks or rarely in the fractures of other metamorphic rocks. The main ore mineral paragenesis for both deposits is galena, sphalerite, chalcopyrite, pyrite and arsenopyrite assemblage, while gangue minerals are garnet, epidote, quartz and calcite. Manganiferous hedenbergitic pyroxene and hematite are only found in the Yenice-Kalkım deposits.
According to EPMA studies, the garnets from Kalkım (Handeresi, Bağırkaç and Fırıncıkdere adits) are grossularite, andradite and hydroandradite in composition, while the garnets from the Çataltepe deposits are andradite and grossularite in composition. Pyroxene minerals are determined as manganiferous hedenbergite, johannsenite and diopside based on XRD, EPMA and Raman Confocal spectrographic analyses. EPMA studies of the ore samples of the Lapseki area show that there are two types of galena: (1) low Ag-Bi-Te bearing galena and (2) high Ag-Bi-Te bearing galena. Trace element mineral data indicate that sphalerite minerals can be classified as two groups according to Fe and Co contents: (1) low Fe and Co bearing sphalerite, and (2) high Fe and Co bearing sphalerite. Pyrite and chalcopyrite minerals are also divided into two groups; (1) Co rich pyrite and chalcopyrite and (2) Co-poor pyrite and chalcopyrite.
Trace element analyses of sulfide minerals in Yenice-Kalkım area show that there is only one type of galena, sphalerite and pyrite formations. Trace element contents of Yenice-Kalkım ores are similar to the low sulfide bearing galena, sphalerite and pyrite minerals of Çataltepe ores. According to both geochemical analyses and EPMA studies, Kalkım area deposits with low Ag-Bi-Te-Fe-Cu-Zn-Co contents seem to be compatible with low Ag-Bi- Te-Fe-Cu-Zn-Co contents in the Lapseki area. In conclusion, EPMA results show that there are, at least, two different ore forming fluids active during the ore forming processes in Lapseki-Çataltepe deposits. Similar metallic element interactions for ore forming fluids in Kalkım area, Pb-Zn-Cu deposits, cannot be found as in the Lapseki-Çataltepe Pb-Zn-Cu deposits.
Large displacements of the Western Black Sea coastline have been encountered during the Late Pleistocene and Holocene due to the Danube Delta’s lobs evolution in time which gradually restricted and finally closed the former Danube Estuary and Halmyris Bay. The notable consequences of this processes were the change of the number and position of the Danube River’s branches discharging mouths and related human activities such as: habitation, navigation, trade, etc. According to ancient historians (e.g. Herodotus in the 5th Century BC, Polybius in the 2nd Century BC, Strabo in the 1st Century BC, Pliny the Elder in the 1st Century AD, Ptolemy in the 2nd Century AD and others), at that time, the Istros River (the ancient name of the Danube River) discharged its waters into the Black Sea through five to seven mouths (branches), among which the most important was the Hieron Stoma (Holly Mouth), identified today as being the Sfântu Gheorghe branch of the Danube.
The combined result of the coastal zone subsidence (estimated amplitude of -2 to -4 mm/y) and the accumulative sedimentary regime within the Danube Delta area place the prospective cultural layer corresponding to late Prehistory – Early Antiquity at a burial depth that now exceeds 4-5 m, the only feasible way to investigate its extension being provided by geophysics. The applicability of the geophysical methods is also very closely linked to the ability of ancient human beings to modify, through their past activities, the habitation environment by generating local petrophysical contrasts. Such contrasts of physical properties (density, magnetic susceptibility, conductivity, etc.), all of anthropogenic origin, on which existence beneath the earth surface all geophysical investigation methods rely on, were only generated when the ancient inhabitants started to use the fire in increasingly larger scale, to excavate, to build (especially when using materials of allochthon origin) and, never the less, to use metallic tools and weapons. According to information gathered on the archaeological sites excavated on the adjacent Northern Dobruja, all these steps toward a better geophysical discoverability have been concluded since Early Bronze Age (3rd Millennium BC). The deep burial of the past cultural layers, set close to the sea level in ancient time, could explain the lack of success of all archaeological works carried out during the last decades toward the discovery of the Histria’s and Argamum’s ancient harbors.
The present position of the inhabited areas suggests the ancient ones were also located along the paleo-branches of the Danube and in the vicinity of the shoreline, at a safe distance from the effects of sea storms. Therefore, the most promising areas in this regard should be of course located in the close vicinity of the Sfântu Gheorghe branch’s paleo-banks, the most important distributor of the Danube River in Ancient times. Here, on several points located on the littoral sector confined by the present day Sfântu Gheorghe and Sulina branches’ mouths, the sea waves bring on the beach pottery remains originating from undiscovered yet antique wrecks caught in the relict beach ridge system and dug out by the intense erosion that presently deepens the seabed by 0.25 – 0.5 m/y.
The possibility that the beach ridges system was born until approximately 500 years AD in the southernmost part of the Danube Delta, that gradually closed the former Halmyris Bay, partly covered today by Sinoie Lagoon and marine shallow waters, to host remains of fortified points and mostly wrecks of the ancient ships connecting Histria and Argamum fortresses with other harbours of the Black and Mediterranean Sea, must be considered. Numerous fragments of pottery brought today by waves on the beach south of Gura Portiţa could be reworked from the erosion submerged beach ridges and clearly sustain this hypothesis. This entire prospective archaeological load, with ages ranging from 8th Century BC to 5th Century AD, contained by the Împuţita - Câşla Vădanei and Coşna - Vadu littoral sectors, supposed to be represented mainly by wrecks of ancient ships, are in an imminent threat of being washed out by the intense erosion that now affects the shoreline as well as the adjacent seabed.
The new results from monitoring of the Krupnik seismogenic area in the Southwest Bulgaria are presented. Special attention is paid to the geodetic analysis using present-day GPS data and seismological modelling of regional stress field in order to constrain the kinematics and dynamics of the region. On the base of the complex analysis of the recent seismicity, geodetic data and fault plane solutions modelling we can conclude that the present tectonic activity in the Krupnik area in SW Bulgaria is associated with the main geodynamic processes in the central part of Balkan region.
The irregular geographic distribution of the raw materials for the energy industry such as oil and gas on the world geographic map creates a problem with their transportation to the end consumer. Nowadays hydrocarbons are transported by tankers or via pipelines. Pipelines are preferable due to a number of reasons. Their advantages make them very attractive and are expressed as follows:
- considerably shorten the distance to the end consumer;
- transport charges for the transit of the products are avoided;
- risks of pollution during this means of transportation are reduced.
Russia and the countries from the Caspian region, the Middle East, the North Sea and Middle Asia are seen as the natural centers of energy resources for Europe. Since these centers of energy resources are available the economic advantage of their use is determined mainly by the methods of their transportation to the end consumers. Two competitive projects - the South Stream and Nabucco – are launched.
Even today we can often hear apocalyptic prophesies of the near end of oil and gas era and appeals to industrial societies to quit the use of oil and natural gas and to start using alternative energy sources and raw materials.
The only outcome is the search for unconventional (alternative) sources of energy, moreover that the prices of these resources will continue to grow in the foreseeable future. The search for unconventional alternative (oil and natural gas) resources and the prospects for their use will bring reassurance for the future of humanity.
New results were obtained over the past 20 years in the sphere of unconventional resources of energy in the Black Sea and the sophisticated technologies that made possible the development of several pilot projects. The topmost is the project for research and production of methane gas from the gas hydrate deposits on the bottom of the Black Sea.
The studies of DSOMS as a complex resource have indicated broad perspectives for their application in the sphere of agrobiotechnologies, nanotechnologies, construction sector, medicine and other spheres. Under the conditions of chronic energy crisis and shortage of quality food products we have to pay special attention to unconventional raw materials and resources of energy. An important factor for the organic farming in Bulgaria is the use of the practically inexhaustible reserves of natural ecological fertilizers found in the Bulgarian
economic zone in the Black Sea.
The Black Sea is a powerful Natural Geobiotechnological Reactor, capable of producing various natural resources. The Black Sea is the biggest generator of H2S in the world and is a global source for the production of hydrogen and sulphur.
The adoption of new, renewable sources of energy and the production of hydrogen and the accompanying products from the hydrogen sulphide extracted from the marine water and the sediments provides the hydrogen energy sector with a new perspective.
The unlimited reserves of H2S in the Black Sea are an important challenge to the modern technologies for production of a new type of energy resources as H2 and the accompanying products (S). The reserves of H2S are evaluated to be between 2.88 and 4.18 billion tons or 169 – 245 million tons of H2 and 2.7 – 3.9 billion tons of S.
Undoubtedly, the suggested energy corridors will contribute to the energy security of the Balkans. However, we should remember the immense potential of the unconventional resources of the Black Sea which studies and utilization will secure the future of the energy sector of Europe.
Acknowledgments: Project: No 02 – 35. National Science Fund Ministry of Education and Science. Bulgaria – Ukraine. “Non-traditional resources from Black sea bottom and their possibilities to use as complex raw material”
Project: No 02 – 337. National Science Fund
Ministry of Education and Science. “Ancient coastlines of the Black Sea and conditions for human presence”
E–W and N–S- trending cross grabens and horsts are the most important structures of Western Anatolia. Çamlıca High is a ~N–S-trending geomorphologic feature with a strong topographical manifestation. This feature, located at the northern tip of the Miocene Yuntdağı Volcanic Complex, is surrounded by Kırkağaç Graben to the east, Soma Graben to the north and Bakırçay Graben to the west. N–S- trending Kırkağaç Fault, E–W- trending Soma Fault and NE–SW-trending Kozanlı Fault set are the marginal faults of this structure. The lignite bearing deposits of N–S- trending Mio–Pliocene basin were elevated by these faults. These deposits and interior part of the High were also dissected by ~N–S and NW–SE- trending faults. To understand the tectonics of the region, field studies were carried out along the marginal structures and interior of the Çamlıca High. Based on the kinematic analyses, performed by using fault-slip data acquired from fault surfaces, the following results were obtained: i) NE–SW- trending faults have been formed under NW–SE extension and the principal stress distribution is σ1= 278°/78°, σ2= 63°/10° and σ3= 155°/7° and the value Φ is 0.184; ii) NW–SE- trending faults have been formed under NE–SW extension regime and the principal stress distribution is σ1= 154°/76°, σ2= 305°/12° and σ3= 37°/6° and the value Φ is 0.335; iii) for the formation of N–S- trending faults (Kırkağaç Fault), ENE–WSW extension is dominant. The principal stress distribution is σ1= 334°/47°, σ2= 187°/34°, σ3= 91°/23° and the value Φ is 0.609, and σ1= 166°/81°, σ2= 335°/9°, σ3= 65°/2° and the value Φ is 0.3 respectively. Under the light of these kinematic analyses, we can conclude that in the region two different tectonic regimes were revealed. The first one is NNE–SSW directed extensional regime resulted from WNW–ESE- trending compression. This tectonic regime was played an important role during the formation of N–S directed left lateral strike-slip faults with normal dip-slip component. The NW–SE- striking faults with normal dip-slip component and related oblique faults were formed due to extension in this regime. The last tectonic regime affecting the region is NNE–SSW and WSW–ENE directed simultaneous extension which enabled the formation of approximately N–S-trending normal faults (Kırkağaç Fault) and E–W-trending normal faults (Soma Fault) controlling especially the boundary of Çamlıca High. This regime additionally reactivated older faults within the region.
The territories of Serbia and Bosnia are very interesting for studies of Mesozoic Radiolaria. Radiolarian ages determined in the Dinarides reveal the following age clusters: Middle to Late Triassic, Middle Jurassic, Late Middle to Late Jurassic, Late Jurassic to Early Cretaceous and Late Cretaceous. No Early Jurassic faunas were found.
In the internal Dinarides radiolarian cherts can generally be found in 3 different tectonic settings: (1) Radiolarian chert sequences which are a part of an ophiolitic mélange formed during the Late Jurassic, underlying obducted (Dinaric or West Vardar) ophiolites of Jurassic age. Within blocks, the radiolarites are often in original stratigraphic contact with basalts. Therefore, such blocks either represent gravitationally emplaced olistoliths, or alternatively, tectonically emplaced slivers. Interestingly, the mélanges often contain Triassic (Ladinian and Carnian to Norian) as well as Jurassic radiolarite sequences, both occasionally associating with basalts. This indicates that the mélange underlying the obducted Jurassic ophiolites also incorporated blocks that represent the remnants of Triassic in age ocean floor (Maliac-Meliata ocean). These occur side by side with blocks that are derived from the obducted Dinaric and West Vardar ophiolites. We interpret the Triassic and Jurassic ophiolites within the mélange to be a part of one and the same Triassic-Jurassic oceanic domain. (2) Jurassic in age radiolarian cherts are also found as an integral part of a still preserved in situ passive margin sedimentary sequence in the footwall of the ophiolitic mélange (East-Bosnian-Durmitor and Drina Ivanjica units). Deposition of radiolarites onto Triassic to Early Jurassic platform carbonates of the distal Adriatic margin indicates subduction of the platform below the CCD initiated during the Aalenian. The onset of subduction predates final obduction which occurred soon afterwards (i.e. at the end of the Jurassic). The radiolarian faunas from different localities in Serbia indicate ages that range from the Aalenian to the Tithonian. (3) Radiolaria may also occur within the so-called “Radiolarite Formation” and within the background sediments of the “Flysch Bosniaque” (or Vranduk Flysch) in Bosnia. The Radiolarite Formation represents a very thick sequence of radiolarites which were separated from their original substratum that belongs to the Adriatic margin. This formation yielded ages ranging from the Bajocian to the Berriasian and the earliest Valanginian. These radiolarites are tectonically overlain by the ophiolitic melange. In contrast to the melange no Triassic radiolarians were found. The radiolarite formation probably represents the detached cover of the East Bosnian Durmitor unit, since both directly underlie the ophiolitic mélange formation. The radiolaria found within the Vranduk flysch, located in the footwall of the Radiolarite Formation are of Oxfordian age and indicate that this flysch basin, which is characterized by ophiolitic detritus, came into existence in the Oxfordian.
Radiolarites contained in Scaglia Rossa type sediments were dated as Campanian. These form the matrix of MORB-type pillow basalts that are part of the Sava Zone. The Sava Zone forms the suture zone between the Dinarides and the Tisza and Dacia blocks. This latter age group provides evidence that the final collision between Adria and Tisza did not take place before Latest Cretaceous times.
The interpretation of geo(morpho)logical phenomena and processes as well as the transmission of geoscientific knowledge to the general public are the essential tasks of geotourism. The proper development of the geotourist sites is a tool for their accomplishment. This paper presents the model of geotourist development which consists of planning and creation of infrastructure (basic and supporting) and the promotion of sites. The basic infrastructure includes the interpretative materials, geotourist trails as well as technical facilities ensuring the safety and comfort of sightseeing. The elements of proposed model are shown on the example of the area of Jasieniowa Mt. (Cieszyn Foothills). The outcrops located in the selected region represent the oldest sedimentary rocks in the Polish Carpathians Flysch, which are the Vendryne Formation and the Cieszyn Limestone Formation. Within the scope of geotourist development, the geotourist trail and information panels were designed, as well as the location of the protective and supporting facilities was proposed.
This article is about results of cadastre of unique geological and geomorphological values in the Castle Hill, in Hungary. The Castle Hill situated in Szanda (528,6 m) has preserved the remnant of the dyke ridge developed during the Miocene volcanism (16-14 Ma) in the Cserhát Mts., the special geological structure and landforms of the dyke and anthropogenic aspects of the mining activity. We would like to show these particular geological structures and landforms with a geological and educational trail extended new stages for tourists today. During our field works, geological and geomorphological values of the Castle Hill have been mapped and surveyed by the Cadastre data sheet of unique landscape values. We have made detailed description of different objects, we have taken photographs of them and we have mapped the route of the new, more detailed geological trail and the topographic situation and landscape values of the stages. Where it was possible, we have measured dips and strikes. Our aim was to cadastre and survey unique geological and geomorphological values of this important nature protection territory. Our investigation has explored 28 new geological outcrops and landform values and these can be built to the route of the older geological and educational trail.
For nearly three decades, mud-mounds were thought to be essentially a Paleozoic phenomenon. Buildups composed of a mosaic of facies, like for instance the widespread Carboniferous Waulsortians and the Belgian Devonian récifs rouges were virtually considered as mud-mound archetypes. It is only since the middle of nineties that the term mud-mound is widely applied to Mesozoic sponge mounds.
In the north-eastern part of Tulcea tectonic Unit from North Dobrogean Orogen, around the Mahmudia village are cropping out Middle Triassic limestones, described in the literature as the first occurrence of Middle Triassic mud-mound deposits in Romania. Associated with zebra and stromatactis typical mud-mound structures, there are some carbonate crusts whose origin seemed to be microbial, but are clues to assume that are similar with cemented grainstone crusts.
The aim of the study is to separate the carbonate microfacies and it will include as methods, optical microscopy, staining and UV fluorescence as keys for sedimentary structures and frequency of allochems, cathodoluminescence (CL), scanning electron microscopy (SEM) and stable isotopes (C, O) analysis for microstructures and diagenetic features and petrography of fluid inclusions for paleoenvironmental conditions. In addition to the optical methods we have also investigated the geochemical composition of selected particles or lamina directly from polished slabs using a microXRF device (Horiba XGT 7000).
Among the carbonate microfacies separated so far, we can include Tubiphytes boundstone, radiolarian and sponge spicule wakestone with stromatactis, bioclastic grainstone to packestone, dolomitised bioclastic grainstone and laminitic mudstones.
The microbial nature of the mud-mound is sustained by the abundance of Tubiphytes, which dominate some areas resulting true boundstones, and the presence of Baccinella, a real microbial product. Metasomatism, dolomitization and cementation which affected the primary fabrics given by early marine diagenesis are proved also by the stable isotope analyses. A deep water environment (internal shelf – 70-100 m water depth) for the mud-mound is suggested by the typical wackestone with sponge spicules and calcified radiolarians or calcisferes.
In situ U/Pb zircon geochronology was carried out on some minor granitoids intrusions from the western Getic domain (Buchin and Slatina-Timis intrusions) and on the swarm of trondhjemitic dikes, sills and small granodiorite bodies from the northern Getic domain - South Carpathians. According to previous petrological studies these intrusions are related to partial melting of a thickened continental crust. Most of the dated zircon crystals are composite, with xenocrystic cores surrounded by multiple overgrowths. Age results on inherited cores of the Buchin and Slatina-Timis intrusions reveal ages from Neoarchean to Late Proterozoic-Cambrian that represent inheritance from old crust. As revealed by ages from zircon overgrowths characterised by oscillatory zoning, the intrusion occurred in the Upper Cambrian-early Silurian. The outer rims of the Buchin zircons record the Variscan metamorphic peak conditions suffered by the Getic basement. The U-Pb ages on inner cores from rocks of the northern Getic domain reveal Paleoproterozoic to Neoproterozoic inheritance. Prevalent ages in zircon cores and rims are in the range 539-428 Ma and seem to date a major component forming the Caledonian crustal basement of the South Carpathians. Scarce but ubiquitous ages of 320-214 Ma on rims overlap the 40Ar/39Ar ages on mylonites from the shear zone and indicate imprints of the Late Variscan dynamic retromorphism. The magmatic intrusion occurred between 110 Ma and 105 Ma in agreement with previous Ar/Ar ages (109-108 Ma).
The Outer Carpathians are built up of a stack of nappes and they are thrusted over the southern part of the North European Platform. The Silesian Nappe occupies central part of the Outer Carpathians and it is built of sedimentary facies represented continues succession of Late Jurassic to Early Miocene times. In sedimentary profile are written successively stages of development of Silesian Unit on the background of evolutionary stadia of the geodynamic development of the Northern Carpathians from syn-, post-rift to synorogenic phase. The best outcrops (legible, good-preserved and accessible for the group of tourists) to examine the Silesian rocks are presented and included into the trail. The sites highlight stratigraphy and sedimentology of Silesian Unit, from Jurassic to Neogene, elements of structural geology, petroleum systems (source rocks, reservoir rocks, seals), geotouristic important objects and history of human activities in the Carpathians, especially of mining and oil industries. The proposed trail traverses the Silesian Nappe in Polish sector of West Carpathians between Kraków, Cieszyn and Ciężkowice area.
The “Bicaz Gorge – Hăşmaşul Mare” Natural Park belongs to the Central Group of the Eastern Carpathians, it is located in the Hăşmaşul Mare Mountains. Due to its natural characteristics, geological, biological, zoological, components, these 2128 ha, in 1980, then in 1995, were denounced as Natural Reservation by the County Council. In 2000, under the 5th law, 3rd paragraph, of National Territorial Planning and Administration, the 6575 ha, of the “Bicaz Gorge – Hăşmaşul Mare” region was declared a Natural Park along with the Lacu Rosu Lake Tourism Resort. In the management of the “Bicaz Gorge – Hăşmaşul Mare” Natural Park we should consider three points of criteria: the management of the inland, the management of border areas (buffer areas), the management of the surrounding settlements, around the national park.
Geomechanical Database developed by Department of Geomechanics at University of Warsaw until recently, collected nearly 200 000 parametric data for Poland’s rock properties as well as respective non-parametric informations (descriptions, graphics) have been collected. The data concern rocks of different age and lithology from various regions of Poland such as Holy Cross Mountains, Sudetes Mountains, Cracow - Czestochowa Upland, Carpathians, etc. The geological regions are subordinated to physical and geographical subprovinces according to the Kondracki division system. The main purpose of Database is systematization and integration of geomechanical rock properties, and their quick search option for large multi-subject data sets. Each component of the Database is identifiable geospatially by means of the material (“rock object”) source location in the geographical coordinate system. With that, all data collected in the Database meet the GIS system requirements and allow co-operating with other information sets within the system.
Based on the unified research procedure adopted by the Department of Geomechanics UW, test results the BDG contains more than 50 000 strength and strain parameters; nearly 100 000 parameters of ultrasonic tests; and more than 40 000 parameters of physical features. Besides in database the data from special tests are collected such as surface roughness for rock fractures; long-term rock deterioration susceptibility under influence of weather or chemical factors. The base deals with data of rocks used currently as raw materials as well as not used recently for industrial purposes for various reasons, for instance due to the location within national parks.
The BDG operates basing on two systems cooperating with each other: The General Database system collecting data on the server, and The System of Applications for viewing the collected data, acquiring new data and for generating reports responding to queries.
The System of Applications consists of three modules: Main Module (MM), Search Module (SM) and Report Module (RM). The Main Module is intended for viewing the entire data base content and for entering new data. The Search Module provides with information selection required by the user. The Report Module presents reports in tables or graphics according to the available options.
The MM structure consists of seven hierarchic information levels in the following sequence: rock origin region, data of the object, rock type, geomechanical parameter, type of examination, data for sample group and data for single rock sample.
Created by Department of Geomechanics the Geomechanical Database operates based on the SQL programming language, which guarantees the system architecture compatibility with different up-to-date data bases. The applied information technologies provide with a full exchangeability of geomechanical data with other GIS systems, where UML, GML, GeoSciML, or XMML language was applied.
The BDG ‘foundation stone’ was the need for a quick search solution for data contained in large multi-subject data sets. Such solution was necessary for publishing the catalogues for Polish rock properties in the regional division. That is why the adopted internal database structure allows presenting selected information in tables or diagrams as well as quickly selecting information for scientific researches thanks to the in-built search module.
The Database layout allows presenting the data either against the background of wellknown geomechanical classification systems, or in needed sets of results. The Database is open and being permanently extended. Parts of the Database are available on the http://www.geo.uw.edu.pl/geomechanika
Besides the detailed photogeological and volcanological maps, the geological photointerpretation on the Oas and Gutai Mountains (OGM) led to the detailed deciphering of the fractural elements which affected the area following the lower Miocene obduction of the Pienidic Units from the Central-East Carpathians. The photogeological interpretation reveals the nappe units disposal of the Pienides system (Botiza, the Wildflysh and some other already mentioned units in the area like Magura, Babesti-Tiacovo, Kricevo, with different spatial and structural disposal from author to author). The slides structure composed by imbricate entities WSW/ENE oriented, with maximal development on 300-400 m width and 1-2 km length within an entity with frequent sequences of discordance is revealed. This image closely fits to the structural model of the frontal Nappes of the Botiza Unit as outlined in the area of maximum outcropping and is extended upon the entire Botiza and Wildflysch Units (conformable to the main entity of the nappe units upon which sporadic outcropping and consistent Upper Miocen sedimentary cover are observed). The development of the crystalline rocks assigned to the Internal Dacides Units vs. Tisia-Dacia as well as of the Cretaceous, Paleogene and Upper Miocene deposits and mostly of the Badenian-Pannonian volcanics have defined a crustal puzzle difficult to decipher, which favored different cartographic and structural interpretations. Based on the photogeologic image, the tectonic interpretation evidenced the major fractures in OGM area: 1. NE Gutai Fault, 2. Dragos Voda-Bogdan Voda Fault, 3. Suior-Baia Sprie Fault (the last two ones being frequently taken one for another), all sinistral strike-slips. We designed also the corresponding sintetic/antitetic faults, as well as other minor faults with considerable structural effects.
The statistic analyses of all fractural alignments quantified by discordant measurable segments (considered proportionally with the value of the fractural amplitude) led to the vectorial representation of the major fractures and their associated syntetic/antitetic secondary faults (1., 2., 3.) advancing the cinematic model (translational and rotational) of the analyzed tectonic block (OGM). The model indicates northeastward movement and counterclockwise rotation (45°-60°) as compensation (retreating) effect of the convergence generated by the oblique collision of the major tectonic plates (East European Plate/African Plate). This cinematic hypothesis (collision at open angle to WSW) seems to infirm the closing sense of the oceanic basin, illustrated by the migration of the foreland basin depocenter in front of the Carpathian arc from W to SE and can be explained only by a specific oblique collision of this tectonic area. The reconciliatory advanced solution of the two interpretative scenarios regarding the Miocene kinematics of the area is a NE peninsula part of the Tisia-Dacia block or of a distinct crustal entity with its own kinematics (Zemplin), at northern joint of the Alcapa/Tisia-Dacia Units. A detailed evaluation of each fractural entity including compressive/distenssive associated assembles (pull apart, positive flower structure, double compressive bands, bypass bends, distenssive and compressive bends etc.) has been performed.
The SE part of the Carpathian-Pannonian region records the cessation of convergence between the European platform/Moesia and the Tisza-Dacia microplate. Pliocene-Quaternary magmatic activity in this area, in close proximity to the ‘Vrancea zone’, changed from normal calc-alkaline type to much more diverse magma compositions at approximately 3 Ma, suggesting a significant change in geodynamic processes. We review the tectonic setting, timing, petrology and geochemistry of the post-collisional volcanism to constrain the role of orogenic processes such as subduction and collision on melt production and migration. The calc-alkaline volcanism (5.3-3.9 Ma) marks the end of normal subduction-related magmatism along the post-collisional Călimani-Gurghiu-Harghita volcanic chain in front of the European convergent plate margin. In South Harghita magma compositions changed at 3 Ma to adakitelike calc-alkaline and continued until recent times (< 0.03 Ma) interrupted at 1.6-1.2 Ma by generation of Na and K alkalic magmas, signifying changes in the source and melting mechanism. We attribute the changes in magma composition in front of the Moesian platform to two main geodynamic events: (1) slab-pull and steepening with opening of a tear window (adakite-like calc-alkaline magmas) and (2) renewed contraction associated with deep mantle processes such as slab steepening during post-collisional times (Na and K alkalic magmas). Contemporaneous post-collisional volcanism at the eastern edge of the Pannonian Basin at 2.6-1.3 Ma was dominated by Na alkalic and ultrapotassic magmas, suggesting a close relationship with thermal asthenospheric doming and strain partitioning related to the Adriatic indentation. Similar timing, magma chamber processes and volume for K-alkalic (shoshonitic) magmas in the South Apuseni Mountains (1.6 Ma) and South Harghita area at a distance of ca. 200 km imply a regional connection with inversion tectonics.
Digital Elevation Models (DEMs) are used for the extraction of land-surface parameters and objects through geomorphometric analysis. Landforms are examples of objects that can be extracted or mapped through wall-to-wall classifications and further used in any application where discrete representations of land surface might serve as variable of interest. In a somehow counter-intuitive manner, most of landform classification systems work through the classification of cells, which could be further clustered to define the borders of objects. This approach is limited in several aspects, including the scattered aspect of classification in the so-called ‘salt-and-pepper effect’, tying the scale of analysis by the raster resolution, difficulties in including topological relationships in classification and also in developing hierarchies of landforms.
This work aims at investigating methods of producing hierarchical mapping of landforms from DEMs. In our approach, homogeneous objects are produced first through image segmentation of DEMs and their derivatives, which are further used as building-blocks in classification/mapping of landforms. Image segmentation is coupled with multi-scale pattern analysis so that the objects are delineated at characteristic scales in a data-driven fashion. Thus, land-surface parameters as derived from DEMs are segmented into relatively homogeneous areas with eCognition Developer® at a range of scales. At each scale level, local variance (LV) is calculated as the mean value of standard deviation of segments. The values so obtained are plotted against scale levels. High values of LV and its rate of change (ROC-LV) indicate scale levels where objects are associated in patterns of land-surface parameters satisfying the condition of maximizing internal homogeneity while maximizing external heterogeneity. The whole procedure has been implemented as an algorithm called Estimation of Scale Parameters (ESP). This procedure produces homogeneous spatial entities with boundaries such that coarser scale entities have precise boundaries within which finer scales entities nest perfectly. This is a condition for developing hierarchical classifications of landform elements.
We are currently investigating two methods of developing such hierarchies:
1. Breaking down complexity through segmentation and successive partitions by nested means. The initially segmented DEM at the scale corresponding to the maximum value of LV is classified in two areas separated by the mean value of elevation. Each area is extracted as independent layer on which segmentations are performed again at the scale indicated by the maximum value of LV and then partitioned at the mean value of another land-surface parameter. This procedure is iterated to produce the third level of the hierarchy. This method is being applied at macro-scale to classify the physiographic units of Africa, as well as at micro-scale to classify landform elements in a flat Dutch landscape for archaeological purposes. Both applications have produced encouraging preliminary results.
2. Semantic modeling. Real-world features and relationships between them (both horizontal and vertical) are conceptualized based on pre-existing knowledge about morphology, morphometry, and spatial context. Characteristic scales selected as above are integrated within a hierarchy where shape attributes and topologies are formalized so that targeted landforms are extracted or classified. This method is being applied to classify glacial landforms.
Foraminifera (single-celled protists that secrete a shell-like test) are among the most abundant organisms in the deep sea (the largest habitat on Earth), and are recognized to be highly sensitive to environmental changes due to both natural and man-induced factors in marine and transitional environments. In particular, the potential of benthic foraminifera has long been recognized for their use in marine paleoenvironmental studies.
The present study focuses on a high resolution analysis of the distribution of benthic foraminifera from one SE Aegean Sea core. The main aim is to describe the impact of the environmental changes on the marine ecosystem through the study of proxies related to the benthic environment. With this goal in mind, one site was selected to investigate spatial and temporal variability as recorded by the benthic microfauna.
Detailed analysis of the benthic foraminiferal content of the core M22-18 in NE Cretan Sea, allowed its palaeoenvironmental reconstruction. The core, 270 cm long, was drilled at 360 m water depth and 39 samples (1 cm thick) were taken. Each sample was washed, sieved at 125 μm and then dried at 60oC. Quantitative analysis was carried out on aliquots separated from each sample by means of a microsplitter, in order to obtain at least 250 – 300 benthic foraminiferal specimens. The number of planktonic foraminiferal tests was also recorded during picking. Based on the faunal counts, benthic foraminiferal numbers (BFN; number of specimens per gram dry sediment) were calculated. This number gives information on the taphonomy of the original living assemblage, the oxygen level, the energy level in which the sediments were deposited and to a minor extent the productivity or organic flux. The percentage of planktonic species in the total foraminiferal association (%P) was calculated as 100*P/(P+B). Raw data were transformed into percentages over the total abundance of benthic foraminifera. Reconstruction of bottom water conditions concerning oxygen content was based on the presence of the dysoxic indicators in the assemblage. For this purpose, the percentage occurrence of the well established redox fauna front dwelling taxa (Bulimina, Uvigerina, Fursenkoina, Globobulimina spp. and Bolivina spathulata/dilatata) which is related to disturbance and/or environmental stress was calculated. Two radiocarbon ages indicate that the studied sequence covers the last 26 ky BP.
BFN remains relatively stable exhibiting low values apart from the basal part of the record where BFN shows an abrupt increase. Planktonic/benthic ratios vary between 16 and 95% of the benthic assemblage.
A decrease in BFN and an increase of low oxygen indicators (infaunal taxa) suggest a strong decrease in oxygen concentrations. Poor ventilation created dysoxic condition allowing the presence of stressed benthic microfauna.
The group of low-oxygen taxa shows high percentages from the bottom to 240 cm, but its abundance strongly decreases between 240 and 40 cm. At 30 cm this group increases again and then remains in constant percentage values in the upper part of the core. The strong decrease of BFN and the increase of the benthic foraminifera deep infauna in the lower part of the core suggests extremely low oxygen values on the sea bottom.
Within a complex scientific program of surveying the Alpine semiclosed ecosystems, the content of seven heavy elements (Sc, Cr, Co, As, Sb, Br and Se) as determined by Instrumental Neutron Activation Analysis in 29 samples of sediments and adjacent rocks from proglacial lake Bâlea (Fagaras Mountanins) and crater lake St. Ana (Harghita Mountains) has been used to establish at which extent these elements could be considered as having an anthropogenic nature. Sc is used as reference elements, as its content was not influenced by any anthropogenic activity. Digital radiography as well as sediments granulometry were also used to get more quantitative data about investigated sediments. Principal component analysis performed in Q as well as R mode was used to evidence the relationship between sediments and neighbour rocks as well as between heavy elements themselves.
Bâlea Lake with an area of 19.5 ha is a typical high altitude (2050 m) proglacial lake while St. Ana Lake area of 4.6 ha and situated at an altitude of 950 m is the unique crater lake in Romania. Although Bâlea as well as St. Ana lakes have different location and origin, they are characterized by a total absence of any source of industrial pollution.
Both lakes collect pluvial water from relative restricted areas (about 234 ha in the case of lake Bâlea and 147 ha for the lake Sf. Ana) so the mineralogical and element composition of their sediments will reflect the geochemical characteristics of surrounding geological formations. Accordingly, the sediments of Lake Bale are expected to reflect the mineralogical composition of the neighbour Suru formation, mainly consisting of metamorphic rocks such as amphibolitic schists, quartzo-felspatic gneissic rocks and mylonites as well as limestones. The sediments of Lake St. Ana, which occupies the bottom of now extinct Ciomatu volcano, mainly consists of fragments of weathered andesite together with an appreciable amount of vegetal detritus, the last one originated from the coniferous an deciduous forests that cover the caldera walls. It is worth mentioning that in the case of Bâlea Lake, the maximum thickness of sediments is not greater than 85 cm, while in the case of St. Ana Lake, sediments thickness is greater than 4 m. This fact reflects the environmental peculiarities of both lakes.
Final data showed that the average content of all seven elements was different for the two lakes, sediments content being relatively closed to average content of surrounding formations. PCA allowed us to establish that in the case of R-mode analysis, all elements form two similar clusters, regardless the lake, while in the case Q-mode analysis, the samples form few clusters, reflecting their location.
At the same, by comparing the sediment contents with those of surrounding rocks as well as with the numerical values stated by Romanian Regulations concerning the Environmental Pollution, it was established that, although their average content was different for the two lakes, all considered heavy elements could be regarded as natural, without any visible traces of anthropogenic influence.
The aim of this paper is the gemmological and microthermometric studies of colour types of topazes (colourless, light pink and blue) from pegmatites of the Volodarsk-Volynski massif (Western Ukraine). These topaz crystals are characterized by the presence of numerous solid and fluid inclusions, mainly of a secondary origin as well as the abundance of micropores. The solid inclusions include mainly albite, tourmaline, Fe-bearing mineral phases and probably organic matter. Among the groups of fluid inclusions, secondary two-phase (liquid-vapour) inclusions distinctly dominate over sparse inclusions of a primary origin. The measured values of temperature homogenization (Th) for selected primary and secondary fluid inclusion assemblages range from 350-380°C and 322°C, respectively. Topaz from Volodarsk-Volynski Massif crystallized during hydrothermal stage in medium temperature conditions. The presence of different secondary and pseudosecondary fluid inclusions together with the traces of necking down processes, point that after the crystallization the topaz was also affected by mechanical, thermal and metasomatic processes.
The Iron Gates (“Porţile de Fier”) Natural Park is located in South-Western Romania and extends along the Danube Gorges and the affluent valleys. The Park is one of the biggest in Romania, having a surface of 115665.8 hectars and including 18 Natural Reserves. The geodiversity of the Iron Gates Natural Park is given by the distribution of a large variety of magmatic, metamorphic and sedimentary rocks, and particularly of limestones of Jurassic and Cretaceous age, affected by a large number of karst phenomena: caves, swallow-holes, gorges, dolina, lapies, uvalas.
The most representative caves in the Park are those from Gura Ponicovei, Padina Matei and Gaura cu Muscă. All of them contain important deposits of fossil bat guano, with a large diversity of phosphate species, including apatite-(CaOH), taranakite, ardealite, brushite, monetite, francoanellite and leucophosphite. These mineral species generally occurs as crusts of yellow cream or reddish brown color deposed on the cave floor or on some speleothems, or, rarely, as earthy masses of white or white cream color. They were identified using a combination of X-ray powder diffraction, Fourier-transform infrared absorption and electron microscopy.
In the upper basin of Mraconia Valley, a system of galleries oppened a tungsten-bearing skarn deposit, which develops at the very contact between crystalline limestones and a porphyric granodiorite of Mesozoic age. The skarn is mainly andraditic, but also contains plagioclase, potassic feldspar, feroactinolite, magnetite, epidote, apatite, vesuvianite and wollastonite. Four stages of mineralization overprint the primary skarn: (1) a high temperature stage conduced to the deposition of scheelite in the mass of skarn; a parallel deposition of quartz and molybdenite on cracks affecting the granodiorite mass is likely; (2) a second hydrothermal stage conduced to deposition of pyrite, chalcopyrite and calcite on the cracks and of impregnations of pyrite and chalcopyrite in the skarn mass; (3) a third hydrothermal stage conduced to the massive deposits of chalcopyrite, pyrite, sphalerite, galena, scarce pyrrhotite and tertahedrite, as veins and lenses in the skarn mass; (4) a low temperature hydrothermal stage yields the formation of bornite and covellite on chalcopyrite but also of hematite (specularite) on magnetite.
Determination of the resistance against freezing water and salt crystallization are two important standard deteriorative tests of building or decorative stones. These tests partially simulate the influence of weather and polluted environment on rocks and check their durability. Impact of the tests on the pore structure of selected natural and agglomerated stone types have been studied by means of optical porosimetry. The optical porosimetry is a technique of a detailed study of porosity in discountinuous materials. Dried porous samples were fully saturated with blue coloured resin, and after hardening, thin cuts were prepared. Effective pores could be well recognized by the colour in thin cuts under microscope (visual analysis - VAO), but also in pictures taken by a digital camera, that were statistically analysed by the computer (digital analysis - DAO). Visual and digital analyses have been carried out before and after the frost resistance tests (25 cycles of freezing/thawing) and before and after the salt crystallisation tests (15 cycles of immersion into a salt solution and drying). Mineral composition, pore network, and selected physical properties have been studied on both, untreated samples and on samples after mentioned laboratory destructive tests. Changes in
rock microstructure predominantly in the pore network due to laboratory weathering tests were identified and illustrated.
Seven types of sandstones from a territory of Slovakia, one type of rhyolite and of travertine, as well as one type of agglomerated stone VASPO simulative various types of natural stones (a Slovak product widely used as exterior and interior cladding stone) have been selected for the research.
Optical porosimetry analyses refer to both realised laboratory tests had destructive effects on studied stones. The degradation due to the salt crystallization was more intensive. The used salt was hydrate phase of sodium sulphate, mirabilite (Na2SO4.10H2O). According to VAO, micro-cracks were formed, predominantly near the samples surface, pore spaces were enlarged by chemical dissolution of some minerals reacting with the salt solution and existing fractures were opened. These visual signs of the stone decay and weakening were confirmed by changes of physical-mechanical properties after tests. Changes in values of total porosity, water absorption, velocity of ultrasonic pulses and uniaxial compressive strength were recorded.
Statistical parameters determined by DAO, i. e. total optical porosity, size-count parameters and erode-dilate parameters, confirmed changes in the rock pore networks after laboratory deteriorative tests.
In general, presented results of both, visual and digital porosity analyses after laboratory degradation tests demonstrate the applicability of the optical porosimetry method in a research of weathering of natural and agglomerated stones or building stone generally, under experimental or natural conditions, especially in cases when the effective (open) porosity of stones is higher than 5 %. More accentuated visual readable demonstrations require the realization a greater number of cycles of freezing/thawing than have been realized in our research.
Acknowledgments: We acknowledge the Ministry of Education of Slovak Republic for funding the projects VEGA 1/4045/07, 1/0499/08 and 1/0413/09
During the field geological mapping and accompanied laboratory studies of the samples for the Basic Geological Map in the wider area of the town of Valjevo (Central Serbia) were distinguished serpentinites, gabbros, peridotites, andesites, diabases and amphibolites. In addition, at one locality within the area (i.e. the village of Danilović, site Suva česma), there was detected one unusual rock in the contact with serpentinite, which is in this paper further determined by the optical microscopic, XRPD and chemical methods, as rodingite.
Rodingite is characterized with a massive structure and granoblastic texture. It has mostly white color, with unevenly distributed concentrations of a green mineral.
Rodingite dominantly consists (over 80 %) of macroscopically white, microscopically transparent, and slightly anisotropic grossular, close to the end member with Grs98Adr2 composition. Grossular appears in a coarse-grain granular form, with size from 0.5 to 1.5 mm.
Green Mg-Al-Fe chlorite occupies interstitials between the grossular grains. This chlorite was most probably formed as secondary phase replacing pyroxene, which is preserved as relic pseudomorphic forms with size up to about 0.5 mm.
Up to now, there were not registered the appearances of such kind of rocks on the territory of Serbia. Nearest sites of rodingites have been previously registered in Bosnia and Herzegovina (11 localities from Brnača at NW to Rijeka at SE; belonging to the Outer Ophiolite Zone), and in FYR Macedonia (1 locality-Raduša; which belongs to the Inner Ophiolite Zone).
According to this classification, discovered rodingite in the area of Valjevo also belongs to the Inner Ophiolite Zone. It occurs in contact with gabbro and peridotite rocks, and most probably originated from veined gabbro by subsequently metasomatic processes.
Vaiscan magmatism is ubiquitos in Western and Central Stara planina, Bulgaria. Its composition is calc-alcaline and essentially acid, as granitoids predominate. Occasionally but with outstanding position, in the Variscan orogenic edifice in the Stara planina, are the rocks of the potassic-alkaline association. From west to east three alkaline plutons crop out: Svidnya, Buhovo–Seslavtzi and Shipka. The plutons intrude Ordovician, Silurian and Devonian low-grade metasediments. The plutonic rocks comprise potassic monzonites and syenites, evolving toward peralkaline acid species (quartsyenite and granite). Based on the isotope and trace elements composition, an enriched source was supposed for the magmas. Their geodynamic position is assumed as postcollisional.
In order to establish the time of formation of the rocks from mentioned plutons ID – TIMS and LA – ICP-MS comprehensive study on zircons were performed.
ID – TIMS analyses for plutonic rocks (syenite) from Buhovo-Seslavtzi display clustering around 340 - 325 Ma, and no reliable isochrone can be defined. LA – ICP-MS analyses yield similar results: 350 – 325 Ma. For the peralkaline dykes from Buhovo-Seslavtzi ID – TIMS age determinations cluster in two time intervals: 318 – 312 Ma and 460 – 435 Ma, with a substantial discordance. LA – ICP-MS results for the dyke rocks are mainly in the interval 470 – 430 Ma, as one analysis gives 310 – 303 Ma. Intrusive rocks from Svidnya plot in two separate time intervals: 315 – 305 Ma and 455 – 440 Ma (ID – TMS). Surprisingly LA – ICP-MS show considerable scattering, as the results cover very large time span: 840 – 388 Ma. Both ID – TIMS and LA – ICP-MS for dyke rocks from Svidnya plot mainly in the interval 460 – 450 Ma. Perfectly concordant ID – TIMS ages for the intrusive rocks from Shipka delineate two intervals: 555-506 Ma and 303 Ma. LA – ICP-MS determinations are grouped in several narrow intervals: 345-335 Ma, 319-326 Ma and 309-307 Ma. At the same time LA – ICP-MS data for dykes from the pluton show much older age: 462-454 Ma.
Ages as 450 Ma could not indicate the time of intrusion of plutonic rocks, because such ages are older than the host metasediments (Ordovician, Silurian and Devonian). Thus, Variscan ages in the interval 350 - 303 Ma would represent the time of formation of the potassic-alkaline rocks. This time interval is too large and it is not possible to determine precisely the position of these rocks in the frame of the Variscan orogeny. Very striking feature is the ubiquitous presence of inherited cores in the studied zircons. It was to some extent unexpected, because zircons are highly soluble in hydrous and peralkaline magmas (according to the experimental data). The fact, that were found complex zircons with strong inheritance even in most alkaline rocks is surprising and requires more attention.
Up to now rest unclear the relationships between the potassic rocks and the calcalkaline granitoids, as well as the successiveness of magma formation. The results show that both rock types are generally contemporaneous, so they belong to one tectonic event. The marked differences in their composition should be attributed to the sources.
The zircons show a multistage origin, attesting for overlapping variable geological events. The frequent presence of inherited cores in the zircon testifies for multiple recycling of older material, involved in the generation of the potassic magmas. At this moment we are not able to specify the nature, origin and mechanism of involvement of these older materials in the source. The results show that material segregation from source and crystallization histories of the magmas were very complex.
In the Małopolska District two underground routes located in old mine workings have been opened to the public. They were developed in the Forecarpathian Basin, in the salt mines in Wieliczka and Bochnia. The salt deposits are hosted in Tertiary - Miocene formations accompanied by anhydrites, gypsum and clays. From the south, these formations are surrounded by the sandstones and shales (flysch), which belong to the Carpathian Foredeep. In both the salt mines in the tourists visit the old mine workings, mainly in the form of spacious chambers and galleries. In those mines the visitors experience a small boat trip across the underground sweet lakes. In Bochnia’s salt mine visitors are also carried by the historical underground railway along 1km distance. Those salt mines are very popular underground health resorts. People ill of breathing system can spend there some time for inhalation.
The research was carried out on shales and mudstones of the Hieroglyphic Beds in the eastern part of the Dukla Unit. Samples of shales and mudstones were examined using optical microscopy, X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The chemical composition of minerals was studied by energy dispersive spectrometry (EDS). In order to obtain clay fractions of <2 μm and <0.2 μm the samples were prepared according to the standard Jackson method. Clay minerals preparations were air-dried, glycol vapour saturated and heated at 330ºC and 550ºC.
Muscovite is the most common detrital mineral and the main component of the analyzed sediments. It occurs as mangled flakes, which underline the lamination of the host rocks. The EDS analyses have revealed fengite character of muscovites, which contain up 5.27 wt% of the Fe2O3. Biotite grains in most cases underwent chloritisation.
The XRD analyses of the <2 μm have revealed the presents of illite, chlorite and mixedlayer minerals: illite/smectite and chlorite/smectite. Illite, in most cases, is the component of cement. Detailed characterization of illite/smectite was based on the diffractograms of the (0.2 μm fraction obtain from the XRD studies of glycol vapour saturated oriented preparation. The type of layer ordering in the mixed layered minerals was established according to the position of 001 reflection. R1 and R>1 are the characteristic types of the ordering in these minerals. They contain up to 30% of smectitic component in their structure. The presence of 1M and 2M1 politypes confirms the existence of both authigenic and detrital illite in the analysed clay material. The EDS investigation showed different amounts of Fe (from 5 to 30 wt% of Fe2O3) in illite or illite/smectite mixed layers.
It was determined that only detrital chlorites appear in the studied sediments. They are often products of chloritisation of biotite. The XRD studies of the <2μm fraction displayed presence of chlorite and mixed-layer chlorite/smectite. It was confirmed during the EDS examinations, which revealed a considerable amount of K, which may derive from smectitic layers. Moreover, the EDS studies showed that chemical composition of chlorites varies considerably and that it is comparable to the composition of chamosite and ripidolite.
The chemical composition of minerals occurring in the studied rocks indicates the complex diagenetic environment. The composition of the pelitic fraction (illite, illite/smectite, chlorite and chlorite/smectite) and a small amount of smectitic component in the ordered illite/smectite interstratifications (R1 and R>1) in particular, indicate the advanced degree of diagenesis.
Acknowledgments: Studies were sponsored by the Ministry of Science and Higher Education (Grant No. N307 2846 33).
Platinum (Pt), palladium (Pd), rhodium (Rh) and gold (Au) were investigated along high-ways of Attica, Greece, with varying traffic, like Katehaki, Messoghion, the intersection between Katehaki, Messoghion and Acharnon avenues, and residential roads, like Pindos and Navarinou roads. Platinum ranges between 110 and 960 ppb in dust samples and from 44 to 820 ppb in soils, Pd ranges between 90 and 1300 ppb in dust samples and from 36 to 1100 ppb in soils. The analysis of dust collected from parts of the roadsides closed to water sewerages reached as high as 2070 ppb Pt and 1980 ppb Pd contents. Gold ranges from 14 to 990 ppb Au (average 230) in dust samples and from 27 to 160 ppb Au (average 95) in soil ones. Any relationship between Au and Pt or Pd is not obvious. The significant fraction of the traffic-related emissions, reaching values over 4 ppm (Pt+Pd), suggest that they may be concentrated into local water systems resulting an environmental risk. Palladium was the most abundant PGE in the grasses ranging from 0.6 to 23 ppb (average 6.8 ppb), Pt ranges between 2.3 and 6.6 ppb (average 4.2 ppb) while Rh is < 0.1 ppb. Average values of the Pd/(Pd+Pt+Rh), Pt/(Pd+Pt+Rh) and Rh/Pd/(Pd+Pt+Rh) ratios decrease from 0.62 to 0.33 and 0.05 respectively, suggesting the Pd>Pt>Rh bioavailability order.
The Gulf of Corinth presents a major scientific and/or socio-economic interest such as the Patras broader area, the Psathopyrgos fault zone which is considered to be a presently active structure, the Rion-Patras fault zone, the town of Patras and the Rion-Antirrion bridge. Patras is the third most populated town of Greece with more that 200,000 inhabitants. The bridge of Rion-Antirrion is 2,880m along (its width is 28 m) and connects the eastern and western Greece. The bridge has been designed and constructed taking into account the increased seismicity of the area. Psathopyrgos fault zone which is acting as a transfer zone between the Corinth and Patras rift as well as the Rion-Patras transfer fault zone are investigated for any detectable ground deformations that could be indicators/precursors of inter-seismic accumulation processes before a main seismic event. The town of Patras is investigated for any detectable ground/buildings deformation due to human impact or geophysical processes. The potential of Rion-Antirrion bridge and surrounding area deformation monitoring is also investigated and assessed.
The studied area presents major difficulties for DInSAR/PSI applications, due to its intense vegetation coverage and abrupt topography presenting, high slopes and shadowing effects. Moreover the nature of the topography and the location of the study area, between Aegean and Ionian seas, result to high precipitation rates and extended cloud coverage. All these characteristics contribute to high decorrelation of the interferometric products. For the estimation of the occurred deformations a series of ASAR/ENVISAT (image swath 2) data are processed by means of PSI and DInSAR techniques, but RADARSAT-2 (ultra-fine beam mode) data are processed only by means of DInSAR technique due to its lack of historical data. The processing is carried out exploiting commercial and in-house software. The medium and high ground resolution added- value products are combined in thematic level and discussed.
The laterite deposits (Fe–Ni-laterite and bauxites) in the Balkan Peninsula are mainly located in the Mirdita–Sub-Pelagonian and Pelagonian geotectonic zones and are of great economic significance. These deposits have been affected by intense tectonism, which has created overthrusting, foliation, folding, and faulting. The investigation of arsenic in laterites is thought to be important for the ferronickel smelting process and the serious affect of the health. Minerals such as iron oxides and pyrite are of particular significance in controlling arsenic mobility, and hence aquifer contamination. Laterite samples from Ni-laterite deposits of Greece (Lokris, Vermio, Edessa, Olympos, Kastoria), Albania (Bitinca and Gouri-Perjuegjiun), Serbia (Rzanovo and Topola), bauxitic laterites and the Parnassos-Ghiona bauxite deposit were analyzed for major and trace elements, including arsenic (As). Arsenic concentrations for all laterite samples from the Balkan Peninsula range from < 2 ppm to a few decades ppm. However, arsenic concentrations for the individual laterite occurrences and deposits from Aghios Ioannis vary significantly from <2 ppm to 2600 ppm. Arsenic in the Parnassos-Ghiona deposit ranges from <10 ppm in typical red colored ore to 900 ppm in yellow-grey colored ore. The latter type occurs along and near faults and constitutes a significant (approximately 30 vol. %) portion of the bauxite ores. They are characterized by the presence of abundant pyrite and micro-organisms. Elevated arsenic contents are mostly associated with Fe-oxides/hydroxides in Ni-laterites, showing enrichment in REE, Co, Ni, Th and U contents, and with Al-oxides in bauxites. The sulphur isotope compositions of Fe sulphides from the bauxite deposit show a range from +10.2 to –30.2 per mil. Most negative values were obtained from grey-coloured ore samples. The organic matter may be related to the source of arsenic and play a major role in controlling the redox conditions, since they can drive the formation of pyrite or Fe-oxides.
The Oltenia Plain occupies ca 8,400 km2 in the SW Romania. With decreasing altitudes from north to south, it includes three W-E elongated subunits: a High Plain (210-110 m elevation), followed to the south by the Danube Terraces (140-35 m) and by the large Danube Floodplain (40–25 m). The fresh groundwater resources are located in the Pliocene-Quaternary formations. The oldest Berbesti Formation consists of lacustrine sands (50-150 m thick) and is overlapped by the Jiu-Motru Formation composed of swampy clays and coal beds with sands insertions (150-300 m). The next lithostratigraphic unit, the Lower Member of the Danube Formation (15-20 m) was built during the Early Pleistocene. Finally, the Danube River moulded Valley own profile. As a result, the higher relief of the Oltenia Plain formed repeated down-cuttings of five-stepped terrace sequence and the Floodplain (Upper Member of the Danube Formation).
The Berbesti Formation is a continuous multilayered aquifer, the hydraulic conductivity of 0.2-15 m/day and specific capacity values of 0.05-4.0 l/s/m.The Jiu-Motru Formation is the discontinuous multilayered aquifer (sands) on the mainly aquiclude clayey-coaly background. The specific capacity values of the lens-shaped tested sands are in the range of 0.01-0.25 l/s/m. The fine sands inserted on the aquiclude background are characterized by low Na+, K+, I+ contents and by higher contents of organic substances, CO2, Fe3+, SO24-, NO2- and Br-. The hydraulic conductivity determined through tests in situ has values between 0.1 and 5.0 m/day. The specific capacity has a large variation interval from 0.2 to 5.0 l/s/m.
The Lower Member of the Danube Formation, represented by the alluvial fan, is discordantly disposed over the previous two formations and bears a continuous extended phreatic aquifer. Its potentiometric contour lines decrease from 200 m to the north to 95 m to the south. Despite the high hydraulic conductivity values (10-55 m/day), being situated at 40-60 m over the local base level of the floodplains, this aquifer discharges on the slopes of the main valleys and has limited resources.
The six mono-layer aquifers bear in the Upper Member of the Danube Formation with 5 terraces and the floodplain of the big watercourses (Danube, Jiu and Olt). Within the Upper Member, there is a N-S increase of productivity (from 1-3 l/s/m in the N strip, to 3-6 l/s/m in the middle one and > 6 l/s/m within the whole Danube Floodplain.
In the eastern subunit of the studied area – the so-called Leu-Rotunda Plain – the Danube Formation is covered by a continuous pile of the Aeolian Formation (30-35 m thick of loose wind-blown silts, clayey sands, fine to coarse sands, having like insertions fossil soils at different levels). Field investigations carried out during April 2010 in accordance to “Climate Change and Impact on Water Supply” Project (see logo) showed that the phreatic aquifer of the Aeolian Formation constitutes the historical source to feeding the people of 15 localities. In large areas, the depth of the water table ranges from 0.5 to 3 m, being vulnerable to estimated climate change. Its resource is contaminated by domestic seepage and fertilizers only within the perimeter of localities. There, the public fountains have around 1,200-2,100 μS/cm Electric
Stavrakia fault scarp occurs along the Heraklion – Mires highway adjacent to Stavrakia and Siva villages, forming the western slopes of a valley. The fault scarp is developed mainly in Tortonian marly, conglomerate and sand intercalations of the Ampelouzos formation and to the north, in Pliocene marls. It is NNE – SSW trending and southeast-dipping at 70º. Its apparent length is about 7.5 km fading out northwards in the river valley, whereas it is geologically unclear if it continues further to the south. In few places flat surfaces can be found with microstructures which indicate a normal sense of movement under an E – W extensional regime, whereas a vertical slip of about 30m can be determined.
Using GIS software, topographic maps of 1:5000 and satellite images we mapped 33 streams and small catchments that drain the footwall of the fault which appears as an elongated range at about 7,8 km at the study area. Basins develop almost perpendicular to the main valley and are elongated in shape, but quite small in size (about 90.000 m2) with high mean slope values. 23 triangular facets of various sizes occur along the range frond formed by stream down-cutting and fault activity. In order to study uplift rates and erosion style of the footwall, as well as fault activity we have calculated three morphometric indices of the footwall catchments, i.e. the hypsometric integral (HI), the basin asymmetry (AF) and the valley width-to-height ratio (Vr). Additionally, we have also calculated the range sinuosity (S) as well as the facet size and mean slope (MS).
Although studied basins have a very small size and thus stream development and erosion are not so profound, several important results can be extracted from the morphometric analyses. Sinuosity value is S=1,11 indicating thus an actively deformed range for the footwall, which is in contrast with the opposite range sinuosity (Se=1,63) occurring at the hanging wall. The hypsometric integral of catchments shows generally values around 0,41 to 0,72 which indicate a high mean topography as a result of high rates of tectonic uplift. The higher value was observed for the B5 catchment at the southern edge of the fault scarp, whereas a strong trend for smaller values appears towards north. The basin asymmetry study didn’t show any certain erosion pattern along the range. Values vary significantly among catchments from AF=80 to 24, however the higher values appear at the southern part and the lower at the northern indicating probably a decrease of erosion rate to the north. Except of few extreme values, the valley width-to-height ratio Vr is relatively very low (<1) in most catchments with an average of Vr=0,5 indicating high incision rates due to tectonic uplift. Rate values are randomly distributed along the range presenting no specific erosion pattern. Morphometric analyses of the facets indicated also that the largest facets appear at the southern edge of the fault scarp, whereas they become smaller towards north. The mean facet slopes, except three, vary generally between 22 – 30º, without presenting any spatial distribution.
All the above observations indicate that: (1) the study area is actively deformed; (2) the higher uplift rates occur about 1 km away from the southern edge of the fault scarp and; (3) uplift decreases gently towards the northern edge. The uplift pattern along the studied fault represents thus a half elliptical structure, leading us to suggest that the fault might extend 5 more kms to the south. Hence, in a possible reactivation its length can be a serious seismic threat for the nearby towns of Heraklion, located 6 kms to the north and the adjacent villages of Stavrakia and Siva.
Treatment of municipal wastewaters (pHinitial 8.2-8.9) with 7.5 g of Hellenic Natural Zeolite (HENAZE) of a grain-size < 1.5 mm, gave overflowed clear water of pH 7.3-7.8, free of odors and improved quality parameters by 89.9-96.7 % for the color, 89.0-98.5 % for the suspended particles, 93.7-97.2 % for the chemical oxygen demand (COD), 92.9-99.3 % for the P2O5 content and 98.3-99.9 % for the NH4 content. The improvement of the quality parameters for the clear water increases with increasing stirring time of the treatment experiments. The correlation coefficient is 0.9423 for the P2O5 content, 0.9323 for the suspended particles, 0.9282 for the chemical oxygen demand (COD) and 0.8854 for the color. The correlation coefficient for the NH4 content and pH are < 0.60. The HENAZE comes from Ntrista stream of Petrota village of Trigono Municipality of Evros Prefecture, North-eastern Greece. HENAZE contains 89 wt. % HEU-type zeolite and exhibit an ammonia ion exchange capacity (sorption ability) of 226 meq/100g. The mineralogical composition and the unique physico-chemical properties, make the HENAZE suitable material for numerous environmental, industrial, agricultural and aquacultural applications, such as: animal nutrition, soil amendment for agriculture, pH soil regulation, greenhouse and flowers substrates, durability and health improvement of lawn, purification of industrial and municipal wastewaters, treatment of sewage sludge, odor control, fishery and fish breeding, gas purification and drying systems, oxygen enrichment of aquatic ecosystems, improvement of drinking water quality, constructed wetlands and wastewater treatment units. The treatment gave as precipitate odorless and cohesive zeo-sewage sludge, suitable for safe deposition and also for the reclamation of agricultural soils. The zeo-sewage sludge produced either from the municipal wastewater treatment or from the mixing of HENAZE and sewage sludge, can be used for the reclamation of agricultural soils. The presence of HENAZE in the agricultural soils, increases the crops yield by 17-66 % and improves the quality of agricultural products by 4-46 %, reduces the use of fertilizers by 56-100 %, reduces the usage of irrigation water by 33-67 %, prevents the seepage of dangerous species into the water environment (e.g., NO3- by 55-92 %), protecting thus the quality of surface and underground waters. The usage of HENAZE in vivarium units and in the animal nutrition increases the production and improves the quality of the relevant products, reduces the feed cost, the animal diseases and medication, the new-born animal’s death-rate and the malodor, converting thus the manure to odorless fertilizer.
The origin and deformation style of the Thrace Basin, NW Turkey represent the target of ongoing debate. Uncertainties are partly due to imprecise knowledge of the stratigraphy of basin-fill sediments. In our contribution we report surface structural data including fault-slip analysis which are important for understanding the origin and structure of the Thrace Basin. Measurements were executed along the northern, north-eastern and south-western margin of the basin. The data from the SW margin also contribute to characterisation of the surface segment of the North Anatolian Fault between the Marmara and Aegean seas.
The earliest detected deformation occurs just SW from the Thrace basin, in the Gelibolu peninsula, along the shore of the Aegean Sea. Folding and faulting of Palaeocene to early Eocene sequence was associated with very low-grade metamorphism. Middle Eocene succession seals the deformation features. Small-scale syn-sedimetary structures (sedimentary dykes and faults) indicate NE-SW to E-W extension along the NE margin of the basin in the Bartonian to Priabonian. Gradual tilting of the beds could occur in map-scale tilted blocks of extensional origin. The repeated normal faulting is deduced from fractures which formed before, during and after the tilting. This deformation process is reflected by progressive transgression on basin margin and intrabasin block margin.
Extensional fractures were also observed in Eocene sequence near the SW margin, in the Ganos Mountains. The age of faulting is not precisely constrained but pre-dates the latest Oligocene – early Miocene folding and related uplift.
All data on early deformation phases point to extensional deformation along both the north-eastern and south-western margin of the basin. Regional geodynamic considerations would agree with fore-arc origin of the Thrace basin.
Before the folding in the Ganos Mountain a strike-slip type deformation occurred during the Late Oligocene - Early Miocene. The E-W compression could induce dextral faulting along the ENE trending southern margin of the Ganos Mountain, the Ganos fault, a precursor of the North Anatolian Fault. This confirms the suggestion that dextral faulting parallel to the NAF could be active already in the late Oligocene-early Miocene.
The large-scale folding itself occurred in a slightly different stress field, in NNW-SSE compression. Progressive fracturing and folding happened in a coaxial deformation process. The folding and related uplift is constrained by fission track data as ~16 Ma.
Post-early Miocene deformation history can be detected south from the Ganos fault, in the Sarköy area. Before the tilting of mid- to late Miocene sediments, a peculiar stress field with SE-NW extension and NNE-SSW compression occurred. This deformation was already observed, but its geodynamic interpretation is not clear. Strike-slip type deformation with EW to NW-SE compression is connected to dextral faulting and folding (transpression) along the Ganos segment of the North Anatolian Fault. This is in agreement with Pliocene-Quaternary dextral faulting along the North Anatolian Fault. A slight change in compression direction can be suspected during the progressive deformation; this non-coaxial character can also be connected to strike-slip faulting.
The purpose of this study is to thoroughly examine the conditions leading to the development of a mesoscale convective complex (MCC) on 24 May 2009 that affected the western and southern Balkan Peninsula, its features and the manifestation of its activity at the surface. To this end, data from a variety of sources were used, such as weather maps, surface records and upper-air soundings, a hailpad network, satellite, lightning, precipitation and radar data. First, the evolution of the system was described, in terms of the track, timing, and areal extent. Second, the synoptic and thermodynamic environment that favored its development was studied. Special features at the surface, such as a cold pool and a mesohigh, were documented by surface observations. Finally, successive satellite, lightning and radar imagery revealed the organization of the system. All data together document well the categorization of this system as an MCC.
Forearc-dipping, orogen-parallel low-angle extensional faults have been described in various orogens, including the Apennines, Italy and, recently, southern-central Crete, Greece. Such a fault system is also present in the central-western Peloponnesus, in the south-western Aegean Arc. It comprises low- and high-angle normal faults which control the western border of Mt Mainalon. The Alpine nappe sequence of the studied area includes the metamorphic rocks of the Phyllites-Quartzites Unit (PQ), overlain by the carbonates and flysch of the Gavrovo - Tripolis Unit, which also overlies the Ionian Unit to the west. The uppermost nappe is the Pindos Unit, which is a sequence of Mesosoic pelagic limestones and clastics, topped by a Paleocene flysch.
Most of the extensional structures were previously thought of as the original thrust contact between the Pindos and Tripolis Units. However, our geological mapping and the cross-cutting relationships among these structures indicate that these are SW-dipping faults – their dip, in other words, is towards the arc- and they downthrow the original Pindos thrust by a few tens or hundreds of meters each. Some of these faults sole into the underlying thick Tripolis flysch, but most of them reach deeper, affecting the contact between the flysch and the carbonate platform. In SW Mainalon we mapped low-angle normal faults that juxtapose the metamorphic rocks of the PQ Unit against the non-metamorphic sequence of the Tripolis Unit. High-angle normal faults found further to the west have truncated or even sole to the low-angle ones. The whole extensional fault architecture has resulted in the Pindos thrust stepping down from altitudes higher than 1000 m in Mainalon, to negative heights in North Messinia and southern Ilia; and the gradual disappearance of the Phyllite-Quartzite metamorphics of Mainalon towards the west.
In the north-west, these faults are truncated by NE to NNE-striking, NW-dipping faults, which transfer the whole fault system towards the north, where it forms the eastern boundary of the Pyrgos graben. On the other hand, the south-eastern members of this fault system are truncated by E-W to ENE-WSW faults, which relay fault activity to the eastern boundary of the Megalopolis basin. All these extensional structures form the eastern boundary of the Megalopolis-Lycaion-Minthi-Tetrazion (MeLyMiTe) and the Pyrgos tectonic depressions, which in turn are separated by the E-W Lapithas horst, at the western end of which the Ionian Unit crops out. The northern and southern boundaries of these tectonic depressions are controlled by oblique-normal faults, perpendicular to the eastern boundary. The throw of these faults increases towards the west and the interplay of all these faults has led to the composite deformation pattern of the MeLyMiTe, which displays extension on its flanks and compression in its centre.
The combination of these extensional faults (which may reach down to the Ionian decollement) with the low-angle floor thrusts of the Pindos, Tripolis and Ionian Units leads to additional ENE-WSW shortening, normal to the Hellenic Arc, west of the Peloponnesus.
We explore the cause of color in the mineral world from the smallest (isolated ions) to the largest (a full crystal). Many mineral colors originate in absorption but occasionally dominates the others, which then merely provide a nuance to the general color appearance.
Isolated ions from the first series of transition elements are undoubtedly the most common cause of color in minerals and gems. They may be a component of the mineral, which is then intrinsically colored, or simply appear as impurities, which is often the case in gems. The major elements involved are vanadium (V), chromium (Cr), manganese (Mn), iron (Fe) and copper (Cu), and to a much lesser extent cobalt (Co) and nickel (Ni). Rarely, rare earth ions may also be at the origin of the tint (mostly cerium (Ce), praseodymium (Pr), neodymium (Nd) and uranium (U)). At planetary scale, iron dominates by the shear volume of rocks it colors. Important factors include the identity of the element, its valence state, the nature of the ligands (mostly oxygen, though), the coordinance (octahedral, tetrahedral or otherwise) and the details of the environment of the ion at the atomic scale (the “crystal field”). For example Fe2+ often gives a bottle-green tinge to minerals (such as peridot and some amphiboles) and Cr3+ emerald-green colors, but both may also induce a purple-red tint (respectively in garnet and ruby).
Color centers result frequently from natural irradiation, and may be treated as pseudoatoms. They could be intrinsic defects (for example a vacancy: the neutral carbon vacancy colors diamond blue). But often, such defects trap impurities. Diamond and fluorine are colored almost exclusively by color centers. One of the most complex examples is amazonite, the turquoise-blue potassium feldspar, colored by a combination of lead and water.
There is a charge transfer when several atoms forming molecular orbitals are involved in light absorption. It may happen between two atoms (oxygen-“metal”) or a more extended cluster. These processes are often very directional, inducing strong pleochroism. They are also very efficient: a small concentration of clusters (10 to 100 ppm) may induce a strong, broad absorption, as is the case for the blue color of sapphire cause by Fe-Ti charge transfer. However, on the contrary to common belief among gemologists, the Fe-Ti charge transfer confers more often a brown tint. The Fe2+ – Fe3+ charge transfer gives a blue color to many minerals and gems (cordierite, some aquamarines and sapphires, blue amphiboles, etc.)
A small number of gems have invariable intrinsic colors explained through band theory, which involves all atoms in the crystal: these could be metallic gems (“marcassite”, actually pyrite), semimetals (graphite, a common inclusion) or semiconductors (cuprite or red sulfides).
Relatively rarely, the electronic structure is not involved, but rather the texture of the mineral, through optical effects. Diffraction is well-known in opal and labradorite, but scattering may be comparatively more common in gems (moonstone, blue chalcedony and agate, blue and violet halite, etc.) or even contribute to some rock tints. Finally, a mineral might color another as an inclusion (hematite makes near-colorless feldspars and quartz red) and poorly crystallized silica (agate, common opal) is almost only colored by inclusions.
This paper presents the diagnosis and interpretation of the sulphatic-evaporitic facieses from the Southern side of Eastern Carpathians, Slănic syncline, in Badenian deposits at Piatra Verde. The succession of evaporitic facieses, with different gravity flow stages facies modelling and basin evolution by means of sequential stratigraphy.
Oaş and Gutâi Mts. are part of the inner volcanic arc of the Eastern Carpathians built up during complex Miocene subduction processes. The suite of different extrusive and intrusive deposits attributed to the felsic, extensional-type volcanism and the intermediate, arc-type volcanism, respectively, comprises abundant volcaniclastic deposits often in connection with coeval sedimentary deposits. Fragmental processes, both explosive and non-explosive, provided the volcanic debris consolidated partially as primary volcaniclastics such as pyroclastic, hyaloclastic and talus breccia deposits.
The pyroclastic deposits identified in Oaş and Gutâi Mts. belong to both felsic and intermediate magmatic suites. The rhyolitic ignimbrites from Gutâi Mts are the exponents of the felsic, caldera-related volcanism. Andesitic block and ash flow deposits occur in Gutâi Mts. and dacitic pyroclastic surge deposits in Oaş Mts. All of them accounting for both magmatic and phreatomagmatic explosions are related to the collapse of growing volcanic structures. The hyaloclastic deposits developed extensively in both Oaş and Gutâi Mts., by the quench fragmentation undergone by andesitic and dacitic lavas emplaced under water. The talus breccias formed on the steep slopes of the volcanic forms in Gutâi Mts., involving the unstable part of the lava pile prone to gravitational collapse.
Most of these primary volcaniclastic deposits are spatially connected with secondary volcaniclastic deposits involving the same loose volcanic debris emplaced by subsequent reworking. Commonly they are interbedded with sedimentary deposits. The felsic volcanism from Gutâi Mts. provided abundant rhyolitic, ignimbrite-related pyroclastics which underwent repeated reworking mostly by mass flow processes, slides/slumps before emplacing in submarine, deep water setting. A similar succession was identified in drill cores in Oaş Mts., but lacking the primary pyroclastics.
The hyaloclastic deposits are usually passing to resedimented hyaloclastites and frequently they suggest reworking altogether with the pyroclastics provided by phreatomagmatic rootless explosions, mostly by mass movements. Thick debris flow deposits and slides or slumps involving the volcanic debris are very common in the geological record of Oaş and Gutâi Mts. The identification and proper classification of these deposits play a major role in understanding the evolution of the volcanic phases, usually followed by subsequent, sometimes dramatic reworking processes. These processes developed in a syneruptive stage seem to contribute much more to the actual volcanic morphology of Oaş and Gutâi Mts than the long lasting post-volcanic erosion.
Fragmental processes, whether explosive or non-explosive, followed by reworking episodes contributed essentially to the build up of the Oaş and Gutâi Mts. They were triggered and controlled by the active tectonics and subsidence as well as by the submarine setting, predominant throughout the volcanic area and the time span of the volcanism.
Besides the geotectonic setting controlling the evolution of the volcanism and the style of eruption, the submarine setting had a major input in some of the fragmental processes and in the emplacement of the volcaniclastic deposits. Considering the processes controlled by the submarine, mostly deep water setting, may be useful when reconstructing the volcanic forms of the Oaş and Gutâi Mts. which is a real challenge as far as most of the volcanic morphology was substantially altered by syn-eruptive subsequent processes followed by post-volcanic erosion.
Middle Eocene – Late Miocene (36 to 11 Ma ) orogenic evolution of north-eastern Outer Carpathians and their foreland basin has been simulated by a kinematic modeling. The model is based upon a new balanced and restored cross section integrating structural (surface and subsurface), seismic and stratigraphic data. It illustrates the internal kinematics of the Outer Carpathian accretionary wedge and the evolution of the wedge-foreland system as a whole.
Restoration of the balanced cross section indicates at least 496 km of post-Middle Eocene convergence between the Inner Carpathians and European Plate, which is more than most of previous estimates. The higher shortening results from application of more accurate thicknesses of lithostratigraphic units in most cases smaller than in previous works. However, we believe this number to be still the minimum value.
The restored section illustrating the Middle Eocene configuration of sedimentary basins is used as a starting point of the 2D kinematic model. Successive stages of the model are constrained by syn-orogenic sedimentary record and reproduced by kinematic algorithms relevant for thin-skinned deformation. Its quality is evaluated by comparison of successive intermediate geometries with available geological data (stratigraphy, provenance and transport directions of syn-orogenic deposits, palaeobathymetric estimates etc.). Ultimate verification is performed by a comparison of the model’s final geometry with the present structure in the balanced section.
The model shows a migration of the Outer Carpathian accretionary wedge towards the foreland and its growth by a successive accretion of new thrust sheets. Position of deformation front in particular time-steps is constrained by stratigraphic data, in particular onset of syn-orogenic deposition, getting progressively younger towards the foreland. However, the kinematic simulation suggests that evolution of the Outer Carpathians cannot be consistently explained by a uniform in-sequence nucleation of successive thrusts. Significant repetitive out-of-sequence thrusting is needed in order to maintain geometry of the modeled accretionary wedge in agreement with existing stratigraphic and sedimentological data as well as with the critical wedge theory. This conclusion is consistent with the present structure of Outer Carpathians, composed of groups of thrust sheets emplaced one on top of the other. The
most important of the inferred out-of-sequence events was an emplacement of the Magura Unit on top of previously deformed and partly eroded Dukla imbricates between 20.0 and 17.5 Ma.
Integration of geometries, kinematics and sedimentation into a single model offered us a possibility for tracing evolution of a convergence rate. Relatively low shortening rate of 10 mm/y between 36 and 25 Ma was followed by its increase first to 19.8 and ultimately to 34.1 mm/y since 19.2 Ma until locking of deformation front at around 11 Ma. However, the variations in convergence rate are not directly reflected in a migration of the deformation front of the Outer Carpathians. Propagation of the leading edge towards the foreland was controlled simultaneously by large-scale processes and a mode of shortening accommodation within the accretionary wedge itself. A shift from frontal accretion to out-of-sequence thrusting was resulting in stagnation of the deformation front, regardless the rate of shortening.
The deduced acceleration of convergence coincides well with an onset of back-arc extension in the Pannonian Basin, commonly related to the roll-back of the subducted lithosphere.
Acknowledgments: Our research has been inspired and supported by TOTAL®. We are grateful for donation of data and permission to publish the results.
An important low sulphidation type epithermal Au deposit occurs at Certej in the southeastern part of the Apuseni Mts., Romania in a small Neogene intramountain basin (Brad-Săcărâmb).
The ore bodies are hosted in Miocene amphibole andesite and Cretaceous and Neogene sandstone, micro-conglomerate and black claystone as well as in their brecciated counterparts. K-Ar ages for the magmatic rocks in the region are between 12.58 – 10.27 Ma. The characteristic mineral association of the studied ore deposit is pyrite, sphalerite, galena, chalcopyrite, tetraedrite-tennantite series minerals, bournonite, arsenopyrite, boulangerite, pyrrhotite and mackinawite accompanied by quartz, calcite and barite. Two ore-forming stages have been distinguished based on 204Pb/206Pb isotope data: 1) syngenetic disseminated Pb-Zn ore in Cretaceous sedimentary rocks, and 2) the main breccia pipe hosted goldpolymetallic ore bodies formed during the Neogene volcanic activity. Hydrothermal alteration products were analyzed by optical microscopy, while selected hydrothermal minerals were determined using XRPD.
Pyritization, silicification, adularization, carbonatization and sericitization are the prevailing hydrothermal alteration types in relation to the main mineralization stage. The XRD study revealed the presence of the following hydrothermal phase minerals: illite, smectite, kaolinite, adularia, barite. Based on K-Ar dating of illite and adularia, the hydrothermal alteration in the Certej occurred between 11.86 (+/-0.52) and 12.29 (+/-1.56) Ma, within the time interval of magmatic activity.
Primary and secondary fluid inclusions in quartz and sphalerite were trapped from a heterogeneous (boiling) fluid. Homogenization temperatures range between 186 – 355.4°C, however, due to the occurrence of heterogeneous entrapment, the temperature of ore forming processes is most probably around 180 – 200°C. The determined eutectic temperatures of the fluid inclusion brines range between -19.3 – -24.4 °C, while freezing point depressions from -4.1 to -0.1°C. The final melting temperature mostly occur between -0.2 and -3.3°C and thus fluid inclusion salinities are in the range 0.35–5.41 eq. wt. % NaCl.
Interest to deep sources of hydrocarbons has appeared after the finding of oil/gas fields in magmatic rocks. For research of oil/gas bearing deep layers, the Polycyclic Aromatic Hydrocarbons (PAH) in basalt rocks of Dead Sea Rift have been studied. The samples were selected both to the north and south from Kinneret Lake in a few ten kilometers distance from basalts, altered basalts, tuffs. Identification of the PAH have been carried out in Biosphere’s Carbonaceous substances Laboratory of Lomonosov Moscow State University (Russia) by "spectroscopy of E. Shpolsky” using a “Fluorat-Panorama” spectrofluorometer (LUMEX, Russia).
GOLAN HEIGHTS.
There are 16 associations of PAH. 4 associations form 51,5% all samples. Most spread associations are: 1) Naphthalene/ Phenanthrene / Pyren (SUM of PAH from 28,3 to 117,5 ng/g, Naphthalene from 51,2 to 80,9%). Presents in Basalts and Tuffs. Locate in West, Center, South /West and South of North Batholith. 2) Phenanthrene/ Naphthalene/, Pyren. (SUM of PAH from 52,6 to 124,5 ng/g, Phenanthrene from 47 to 60,2 %). Presents in Basalts. Locate in West, Center, South /West and South of North Batholith. 3) Naphthalene/Phenanthrene/ Benzo(ghi)perylene (SUM of PAH from 53,3 to 87,5 ng/g, Benzo(ghi)perylene from 1,9 to10,5 %). Presents in Basalts. Locate in West and South/West of North Batholith. 4) Naphthalene/ Pyren/ Chrysene (SUM of PAH from 81,1 to 95,5 ng/g, Chrysene from 0,25 to 0,52, Pyren from 4,6 to 57,3). Presents in Basalts. Locate in the Center of North Batholith. All 4 associations belong to higher temperature formations (Naphthalene and Phenanthrene). And Pyren and Benzo (ghi) perylene belong to lower temperature formations. In the same time existence such components as Phenanthrene, Chrysene, and Pyrene probably pointed on migrations of Hydrocarbons from depth.
BASALT WEST.
There are 8 associations. 3 associations form 70% all samples. Most spread associations are: 1) Naphthalene/ Phenanthrene/ Pyren. Presents in Basalts. Locate in: West of North Batholith; West of South Batholith; West of separate dyke. 2) Naphthalene/ Phenanthrene. Presents in Basalts. Locate in: West of North Batholith; West and South of South Batholith; West of Separated dyke. 3) Naphthalene/ Pyren. Presents in Basalts and Tuffs. Locate in: West of North Batholith; West of South Batholith; in West of separated dyke.
All 3 associations belong to higher temperature formations (Naphthalene and Phenanthrene). And Pyren and Benzo (ghi) perylene belong to lower temperature formations. In some samples Phenanthrene, Chrysene, Pyrene was identified.
Presence of diverse groups of PAH in the rocks of highly fractured and secondary basalts alterated, point at migrations of Hydrocarbons through faults from possible deep reservoirs/source of Dead Sea Rifts.
The Slovenian Basin represents a Mesozoic deep-water sedimentary environment, located on the south Tethyan passive continental margin. Its history can be divided into two parts: from the initial opening during late Anisian/Ladinian to progressive shallowing in the Carnian, and from a marked deepening, which started in late Triassic/early Jurassic, to the final closure at the end of Cretaceous. Upper Triassic deposits comprise Carnian “Amphiclina beds”, followed by Norian-Rhaetian “Bača Dolomite”, which in the northernmost part of the basin laterally passes into non-dolomitized Slatnik Formation.
The “Bača Dolomite” due to strong late-diagenetic dolomitization represents a very poorly investigated segment in the history of the Slovenian Basin. In order to resolve its depositional characteristics, an incompletely dolomitized succession outcroping on Mt. Slatnik (south-eastern Julian Alps, W Slovenia) has been studied in details. The Mt. Slatnik section structurally belongs to the Tolmin Nappe, which is a part of easternmost Southern Alps. The Norian age of the “Bača Dolomite” in this section has been established on the basis of superposition, foraminifers and conodont data.
The Mt. Slatnik section starts with 75 m of mud-supported massive channelized slump breccias with laminated intraclasts and chert clasts, indicating an inner apron environment. They are followed by 19 m of medium-thick amalgamated, partly bioturbated beds of marly dolomite with parallel lamination and chert nodules. Non-dolomitized parts are represented by spiculite packstone. Slump breccias are rare. Deposition took place in an outer apron. The following 10 m of the succession are composed of several up to 1 m thick sedimentary cycles starting with thin-bedded cherty limestone and ending with more prominent marlstone layer. Limestone is texturally thin-shelled bivalve coquina pack- or wackestone, or very finegrained peloidal and fine-grained peloidal-bioclastic packstone. In the latter grains are mostly of shallow-water origin. These beds are interpreted as distal turbidites intercalated within basin plain deposits. In the next 23 m the marly content markedly decreases. Beds are thicker. Among dolomite, limestone beds are preserved, texturally being mudstone or wackestone, with intercalated very fine peloidal and fine-grained peloidal-bioclastic packstone. Amalgamation is common as well as chert nodules and sedimentary structures, namely normal and inverse grading, parallel, cross and convolute lamination, geopetal structures and load casts. These beds were deposited in the outer apron. Massive clast-supported slump breccias in the next 13 m contain laminated dolomitic intraclasts and chert clasts. The first are concentrated near the lower bed-boundary and sometimes imbricated. Breccias indicate an inner apron environment. Next 20 m of medium-thick dolomite beds with subordinate laminated limestone with wackestone to packstone textures again mark the outer apron. They are followed by 17 m of dolomite with chert nodules, indicating deposition on a basin plain. Dolomite beds in the next 80 m thick interval in places exhibit convex lower boundaries, indicating occasional slumping in the lower part of this interval. Upwards, limestone predominates. Amalgamated beds show parallel, cross and convolute lamination, and grading. Texturally they are wacke- to packstone. This interval shows deposition in an outer apron. Mudstone in the uppermost part could indicate the beginning of the next deepening phase.
In summary, the bulk sedimentation of the Norian “Bača Dolomite” took place via slumps and sediment gravity flows. Two “retrogressive-progressive” (?) cycles can be deciphered, each with shifting of the place of deposition from an inner apron to basin plain environment.
The Caucasus represents complicated polycyclic geological structure involving mountain fold systems of the Greater and Lesser Caucasus and adjacent foredeeps and intermountain troughs. Paleomagnetic, paleokinematic and traditional geological data indicate that within the oceanic area of Tethys in geological past relatively small continental or subcontinental plates (terranes) were situated having various geodynamic nature and characterized by specific lithologic-stratigraphic section and magmatic, metamorphic and structural features. During the Neoproterozoic, Paleozoic and Early Mesozoic they underwent horizontal displacement in different directions within the oceanic area of Proto-, Paleo-and Mesotethys (Neothetys) and as a result of Variscan, Early Kimmerian, Bathonian and Austrian orogeny underwent mutual accretion and ultimately joined the Eurasian continent. South of the Scythian platform (Sp) the Greater Caucasian (GC), Black Sea-Central transcaucasian (BC), Baiburt-Sevanian (BS) and Iran-Afghanian (IA) terranes are identified in the Caucasian segment of the Mediterranean mobile belt, which in geological past represented island arcs or microcontinents.
In modern structure they are separated by ophiolite sutures of different age, which mark the location of small or large paleooceanic basins. All terranes of the East order (superterranes), as well as the southern edge of Sp are characterized by manifestation of polymetamorphism, though in various terranes, separate stages of regional metamorphism established by geological observation, but mostly confirmed by isotopic-geochronological data (K-Ar, Ar-Ar, Rb-Sr,U-Pb, Sm-Nd), became unequally apparent. For instance, Grenville regional metamorphism is observed only in GC (T - 700-750C, P - 3.2-3.5kbr), BC (T - 600-700°C, P - 3.2-3.5kbr) and IA (T - 500-550°C, P - 3.8kbr) terranes, whereas the Baikalian - only in Sp (T - 300-400°C,) and IA (T - 460°C, P - 4kbr) terrene. Late Baikalian metamorphism took place only in GC (T - 430-540°C, P - 3.3-3.5kbr) and BC (T - 540-570°C, P - 2.5kbr) terranes. Caledonian regional metamorphism strictly characterizes Sp (T - 700 ± 50°C, P - 17.8 ± 4kbr) and GC (T - 500-620°C, P - 2.2-2.8kbr) terranes. Early Variscan (Bretonian) metamorphism is observed almost in all terranes of the Caucasus: GC (T - 350-630°C, P - 1.35-2.7kbr), BC (T - 320-380°C, P - 1.5-1.8kbr), BS (T - 330-550°C, P - 1.5-2.6kbr) excluding IA terrene, and southem edge of Sp. Late Variscan metamorphism also comprises almost the whole Caucasus (T<430°C, P<1.4kbr) excluding Sp and IA terranes. Within separate terranes, as well as in Sp, synchronously or almost synchronously with principal stages of metamorphism (connected with main phases of tectogenesis) formation of pre-synand postmetamorphic granitoids of different type took place. Based on a vast analytical material concerning the petrogenic and rare elements in pre-Alpine granitoids of the Caucasus, it is established that the Neoproterozoic granitoids, occurring in all terranes excepting SP, are represented mainly by the crustal and upper crustal formations of the subduction mantle-crust and mantle island arc categories.
The Late Baikalian granitoids are developed in GC and BC only. They are represented by the subduction mantle-crust and crust-anatectic categories. The Caledonian granitoids, cropping out only on SP, are represented by the subduction mantle-island arc formations formed with participation of the mantle and lower crustal material, and also subduction granitoids emerging due to melting of the immature continental crust. The Bretonian granitoids appear only in GC and BS. Granitoids of GC as whole correspond to the upper crustal granitoids of the other regions of the world, whereas the granitoids of BS are represented by the subduction formations of the mixed mantle-crust category; sialic part of the continental crust has an insignificant role during their formation. The late Variscan (Sudetian) granitoids are present in all terranes, excluding IA. The Sudetian orophase is the time of post-metamorphic potassium granitoid formation and consequently of true continental crust. The Sudetian granitoids of all exposures are characterized by similar composition, pelrogeochemical parameters and geodynamic conditions of formation. Their major part corresponds to the upper crustal formations, and the minor part - to the common crustal ones. The observed occurrence of different age and diversity of endogenic activity in various terranes of the Caucasus show asynchronism of episodic activity of subduction zones on different sides of oceanic basins separating these terranes.
Heraklion is a fast-growing urban centre where knowledge of active faulting is necessary for city planning and infrastructure projects. Neotectonic faults (not all necessarily active at present) most probably traverse the built-up coastal part of Heraklion, but they require subsurface geological and geophysical studies to be precisely located and characterised. In the frame of a research project assigned to the Institute of Geodynamics by the Heraklion Municipality, we made detailed geomorphological and geological observations in the coastal area of the Tripiti Hill, where previous workers report a NNW-SSE trending, WSW-dipping, presently active normal fault crossing the port of Heraklion as well as a densely built-up part of the city. Based on our observations, we conclude that this fault does not exist. In support of our conclusion, we discuss: (1) the nature of a steep contact between Neogene bedrock and Quaternary deposits exposed at a roadcut along the coastal avenue, (2) the depositional environment of Quaternary deposits at the above outcrop and surrounding area, (3) the buried relief and stratigraphic features exposed in a trench excavated by previous workers across the alleged fault trace, and (4) the geomorphological context of coastal deposits and marine terrace remnants used by previous workers for fault slip rate estimation. This case study is presented as a vivid example of the importance Geomorphology and Quaternary Geology have in studies of active faulting.
Isotopic studies on carbonates and lake sediments are a major source of paleoclimate and paleoenvironment data from continental records. Studies on recently deposited travertines from Northern Slovakia were basis for correlation of isotopic record with recent climate changes.
Many sites with presently deposited travertine are located in North Slovakia and they annual sedimentation rate is up to several tens of centimetres. The geochemical and isotopic measurements give possibility to precise description of deposition process and its relation to air and water temperatures. This was useful for revision of paleotemperature records obtain from fossil travertines in the region.
Two sets of data were collected for realisation of the project: water samples of stream flows through travertines cascades and samples of travertine. Actinide activity and stable isotope composition were measurement for both sets of data.
The results point to: (1) a high sedimentation rate of travertines – 1 mm of sediment is deposited during 2-4 days, (2) a high activity of actinides in water and travertine samples, (3) changes of actinides’ activity during the year, probably related to changes in metabolism of algae growing in travertine cascades, (4) no correlation between oxygen isotopic composition and changes in air temperature in annual scale.
The Nestos Shear Zone (NSZ), mostly on the Greek territory, is recognized as one of the major structures of the Rhodope Metamorphic Complex (RMC). It consists of a thick NNE-dipping pile of mylonites with top-to-SW kinematics encompassing the contact of the ‘Sidironero Unit’ (SU) onto the ‘Pangaeon Unit’ (PU, the lowest exposed unit of the RMC). For most authors, the top-to-SW shear fabric of the NSZ reflects synmetamorphic thrusting.
We carried out a structural, petrological and geochronological (U-Pb and 39Ar-40Ar) study of the NSZ. Inverted metamorphism is confirmed and is found to be coeval with top-to-SW shearing. The whole SU (including its base, overlapping with the NSZ) experienced the conditions of advanced partial melting at T > 650°C. Leucosomes that locally crosscut the main fabric crystallized between ≥ 50 and ca. 40 Ma (U-Pb zircon and monazite ages), just before cooling of the metamorphic pile. This shows that at least part of the migmatization is not an old event but is part of the syn-shearing metamorphic evolution. In contrast, rocks of the PU right beneath the SU do not show any evidence that they ever reached the conditions of anatexis. In orthogneisses, microstructures document amphibolite facies shearing. Although relatively rare, metabasites and Grt-bearing micaschists keep the record of a prograde metamorphic path culminating at T ≤ 620°C (at P ~ 8-10 kbar). Thus, higher-grade rocks were emplaced onto lower-grade rocks during top-to-SW shearing, attesting for synmetamorphic thrusting along the NSZ. Hornblende 39Ar-40Ar single-grain plateau ages from the NSZ are between 39 and 37 Ma, which we interpret as dating amphibolite facies shearing. Later strain increments have produced greenschist facies mylonites and ultramylonites subconcordant with the earlier fabric and with identical kinematics. White mica 39Ar-40Ar single-grain plateau ages from these rocks are between 36 and 33 Ma, which we interpret as dating mylonitization. With respect to peak conditions in the PU, this deformation occurred at lower grade conditions, therefore inverted metamorphism cannot be invoked in this case. Nevertheless, several lines of evidence indicate that this deformation reflects thrusting as well. Consequently, our study documents persistent synmetamorphic thrusting along the NSZ as late as ca. 33 Ma. This is consistent with results obtained from the Chepelare Shear Zone, in the Bulgarian Central Rhodope (Gerdjikov et al., this volume), and contradicts the view that post-orogenic extension was already active in pre-Oligocene times in the northern Aegean. Our analysis of the RMC further indicates that post-orogenic extension
did not start before ca. 27 Ma. Hence, it started at about the same time than it did further south in the Cyclades and Menderes region, at variance with the statement in some recent geodynamic syntheses. The picture arising from the RMC is consistent with a change in the geodynamic setting of the whole Mediterranean at around 30 Ma, from strongly compressional (i.e. Alpine collision) to a situation dominated by trench retreat and postorogenic extension.
For the detailed stratigraphic division of the Upper Cretaceous sediments of the Zhinvali-Gombori subzone of the Mestia-Tianeti zone GCFS, and for specifying the volume and age of the formations, in the facies of Sadzeguri-Shakhveli and Zhinvali-Pkhoveli nappes the sections of the Ksani and Aragvi river basins (the rivers Aleura, Sakanaphe, Arkala, Didi Jakha, Patara Jakha; near the villages Sadzeguri, Korinta, Ananuri, Muguda, Avenisi, Pavleuri) have been studied.
Detailed study of the assemblage composition of calcareous plankton contents (calcareous nannofossil and planktonic foraminifera) of the Late Cretaceous sediments of the Zhinvali-Gombori subzone of the Mestia-Tianeti zone of the Greater Caucasus fold system (GCFS) has been carried out for the first time in this region to define biozonation. Within the limits of the Cenomanian-Maastrichtian 9 small foraminiferal and 19 nannoplankton biostratigraphic units (zones and subzones) have been established. Here are specified volume and age of lithostratigraphic units (successions) composing the Upper Cretaceous of the Mestia-Tianeti zone of GCFS: the Ukughmarti succession – СС9 (Early Cenomanian); the Ananuri succession – СС9-СС11 (Early Cenomanian-Early Turonian); the Margalitisklde succession – СС12-СС13 and planktonic foraminifera zones Marginotruncana pseudolineiana-M. lapparenti and Marginotruncata sigali. (Late Turonian-Early Coniacian); the Eshmakishevi succession - СС14-CC19 (Late Coniacian-Early Campanian) and zones Archaeoglobigerina basquensis and Globotruncana arca (upper part of the succession); the Jorchi succession – СС20-СС25а (Middle Campanian-Lower Maastrichtian), in the sediments of СС22с is established the small foraminiferal zone Globotruncana ventricosa-Rugoglobigerina rugosa; the Sabue succession – СС25b-СС26 and foraminiferal zone Gansserina gansseri (Late Maastrichtian).
The analysis of the Late Cretaceous nannoplankton and foraminifers association of the Zhinvali-Gombori subzone of the Mestia-Tianeti zone of GCFS has shown the existence of four sedimentary cycles: Cenomanian-Early Turonian, Middle Turonian-Early Campanian, Late Campanian-Early Maastrichtian and Late Maastrichtian On the territory of Georgia contained in the Late Albian pool there were is established some large sites of a land, where the Cenomanian sediments with the washout rest on the underlying formations. In the Cenomanian-Early Turonian there was a basin of isolated, regressive sea in the southern part of the moderately cold-water belt. From the Late Turonian the boundary between the warmand moderately cold-water belts moved to the north. Transgression that started in the Late Turonian lasted till the Early Coniacian. In the middle part of the Early Coniacian is outlined shoaling of the basin. From the Late Coniacian to the end of the Santonian sedimentation took place in the shallow, calm marine basin. The omission of the nannoplankton СС19, СС20, СС21 and СС22a, b zones from the sections of the Zhinvali-Pkhoveli nappe and the analysis of the redeposited forms enables to admit break in sedimentation caused by Early Campanian regression and Late Campanian transgression. At the end of the Middle Maastrichtian took place a short-term regression that was replaced by the Late Maastrichtian transgression.
In the High Karst Nappe in southern Montenegro radiolarites of unknown age topped the Upper Anisian Bulog Limestones (Late Pelsonian to Illyrian) in the investigated sections Boljevici near Virpazar and Obzovica on the road Budva to Cetinje. Radiolarian faunas from the radiolarites as well as conodonts from the overlying red hemipelagic limestones prove an Illyrian age of the radiolarites. The time interval of the deposition of the up to 5 m thick radiolarite successions is relatively short and started and ended in the Illyrian.
In the section Boljevici the hemipelagic succession starts with red hemipelagic Bulog Limestone on top of shallow-water limestones equivalent to the Ravni Formation (Dedovici Member) in the Outer Dinarides or the Steinalm Formation in the Eastern Alps/West Carpathians. The drowning of the platform sediments can be dated by the occurrence of Nicoraella germanicus, Nicoraella kockeli, Gondolella bulgarica, and Gondolella cf. bifurcata as Late Pelsonian; these conodonts derive from the overlying Bulog Limestones. Deposition of the Bulog Limestones in this section lasted until the Illyrian, proven by the occurrence of Gondolella excelsa, Gondolella trammeri, and Gondolella liebermanni. Following radiolarians from the reddish laminated radiolarites on top of the Bulog Limestones prove an Illyrian age (Spongosilicarmiger italicus Zone to lower part of Ladinocampe multiperforata Zone; equivalent of Reitziites reitzi Ammonoid Zone): Baumgartneria cf. retrospina, Cryptostephanidium cornigerum, Oertlispongus inaequispinosus, Paroertlispongus multispinosus, and Triassocampe scalaris. The directly overlying sequence of the radiolarite is not exposed, but upsection follow Late Ladinian to Early Carnian shallow-water limestones and dolomites.
In the section Obzovica the drowning sequence of the carbonate platform is not exposed. Red limestones below the radiolarite succession belong to the Bulog Limestone. Upsection follows a five metre thick succession of red and partly grey well-bedded radiolarites. From the red radiolarites we isolated a well preserved Illyrian radiolarian fauna (Spongosilicarmiger italicus Zone; equivalent of Reitziites reitzi Ammonoid Zone) with: Baumgartneria bifurcata, Baumgartneria cf. yehae, Cryptostephanidium cornigerum, Eptingium manfredi, Eptingium ramovsi, Falcispongus calcaneum, Hozmadia sp., Oertlispongus inaequispinosus, Parasepsagon asymmetricus, Pseudostylosphaera japonica, Pseudostylosphaera tenuis, Spongostephanidium sp., Triassocampe deweveri, Triassocampe scalaris. In the upper part of the radiolarite sequence up to ten centimetre thick intercalated hemipelagic filament-bearing limestones are of latest Anisian to earliest Ladinian age, proven by the following conodonts: Gondolella excelsa, Gondolella trammeri, and Gladigondolella tethydis. Upsection the radiolarian cherts decrease rapidly and the following hemipelagic red limestones are of earliest Ladinian age, proven by conodonts. These red limestones pass continuously into grey hemipelagic limestones of Late Ladinian age (with Gladigondolella tethydis and Gondolella foliata), topped by shallow-water dolomites of Late Ladinian to Early Carnian age.
This short-lasting latest Anisian radiolarite event in the succession of the High Karst Nappe is contemporaneous with the complete demise of shallow-water carbonate production in the whole western Tethyan realm and corresponds to the onset of the first radiolarites on the Neotethys Ocean floor, as proven in Albania and northern Croatia as well as in the Meliata Unit in Slovakia and Hungary. In the late Anisian the huge parts of the passive margin facing the newly formed Neotethys Ocean became flooded and volcanic ashes and radiolarites were deposited in the whole Dinarides reaching the palaeogeographic realm of the High Karst Nappe. Obviously, volcanics in our sections are preserved only as some thin intercalations of metabentonites. The latest Anisian radiolarite deposition corresponds also to the onset of intense volcanism in the Dinarides more to the north and in the southern Alps in Italy. The studied successions are nice examples of short-lived hemipelagic basins that formed on continental margin during the late Anisian rifting and were later, in the Ladinian and Early Carnian, completely infilled with sediments of prograding carbonate platforms.
Eocene-Oligocene sequence of the northern Ukraine consists of diversified, mainly non-calcareous clastic deposits representing following lithostratigraphic units: Kanev Formation (?Ypresian), Buchak Formation (Lutetian), Kiev Formation (Upper Lutetian Bartonian), Obuhov Formation (Priabonian), Mezhigor Formation (Rupelian) and Bereka Formation (?Chattian).
We compared results of palynofacial analysis (i.e., composition of organic remains of marine and terrestrial origin) and taxonomical diversity of aquatic palynomorphs representing both marine and freshwater taxa. Our palynological analysis revealed variable sedimentological settings of these deposits reflecting various palaeoenvironments.
The oldest investigated strata (the Kanev Formation) contain high ratio of marine dinoflagellate cysts (occasionally up to 90%) pointing to marine environment optimal for development of rich and diversified dinoflagellate flora during the Early Eocene (Ypresian).
Younger strata (the Buchak Formation) contain already palunofacies that could be interpreted as indicative to deposition in more proximal setting than Kanev Formation. It contains higher ratio of terrestrial plant remains, whereas dinoflagellate cysts are dominated by near-shore species Homotryblium tenuispinosum.
Bartonian strata (the Kiev Formation) yieldrich and diversified dinoflagellate cysts assemblages, which are indicative for marine environments. Taxonomical richness and occurrence of an oceanic genus Impagidinium suggests offshore sedimentary setting during Bartonian. A gradual sea withdraw can be interpreted as Priabonian: diversified assemblages in basal part of the Obuhov Formation, become relatively impoverished in the upper part of this unit where representatives of the genus Deflandrea and Prasinophyta algae (Pterospermella, Tasmanites) occur. Land-influences are markedly evident in Lower Oligocene Miezhigor Formation: palynofacies is dominated by sporomorphs and land plant tissue remains. Moreover, freshwater algae also frequently occurs.
Preliminary comparison of our data with palynology of coeval strata from Polish part of epicontinental sea and Carpathian basins suggests that these basins were presumably connected during the Middle and Late Eocene. This is based on general taxonomical composition similarity of our assemblages to those known from Middle and Upper Eocene strata of the Flysch Carpathians (e.g., the Variegated Shale, the Hieroglyphic Beds). Throughout Early Oligocene, however, epicontinental basins were rather separated from Carpathian ones. Dinoflagellate cysts from the Miezhigor Formation are relatively diversified, whereas the ones from coeval Menilite facies of the Carpathian basins are almost absent.
Acknowledgements: This research was supported by the Polish Ministry of Science and Higher Education research grant N N307 107035.
The Neogene-Quaternary Central Anatolian Volcanic Province (CAVP) is characterized by widespread polygenetic and monogenetic volcanism. About 800 monogenetic volcanoes were identified within the CAVP and these mainly include scoria cones and related flows (basaltic and andesitic), with subordinate maars (of both basaltic and rhyolitic composition), and domes (generally rhyolitic in composition).
Despite the occurrence of q-normative, ol-hy-normative, and ne-normative basalts, CAVP monogenetic basalts (s.l.) have been generally considered as alkaline. Based on this fact, they are recently evaluated as tholeiitic, transitional, and mildly alkaline (<5% normative ne), respectively. Similar patterns and HFS anomalies of monogenetic basalts on mantlenormalized diagrams to CAVP calc-alkaline lava flows from the polygenetic volcanoes were also noted. These andesitic-dacitic lava flows from the CAVP stratovolcanoes display orogenic trace element fingerprint, reflecting enrichment of their source regions by subduction-related fluids. So, this brings about the need for revisiting the source characteristics of CAVP monogenetic basalts. Compilation and re-evaluation of all available geochemical data from previous studies, and interpretation of our own data from monogenetic
volcanoes enabled us reviewing source characteristics of monogenetic basalts in CAVP.
CAVP monogenetic samples are transitional to calc-alkaline according to their Zr and Y contents. All CAVP monogenetic basalts display similar variably enriched LIL/HFS patterns and HFS anomalies on mantle-normalized diagrams. They all have incompatible element ratios intermediate between orogenic andesites and within-plate basalts. High La/Nb (>1.6), Al2O3/TiO2 (10-17) and low Sm/Yb ratios (<2.5) imply that the melts must have been derived from shallow depths (<80 km), that is within the lithospheric mantle, just like the calc-alkaline volcanics of CAVP. There is also evidence which might account for crustal contamination such as highly variable range in HFS and other incompatible element ratios Zr/Nb, Y/Nb, La/Yb, and presence of slight negative Ba anomaly on multielement diagrams. Presence of U peaks on mantle-normalized multielement diagrams for most monogenetic CAVP basalts, and variation in 87Sr/86Sr ratios reported for monogenetic volcanoes in the western part of CAVP imply crustal contribution as well.
The driving mechanism for generation and ascent of Neogene-Quaternary volcanism in the CAVP is the transtensional and rotational tectonics in central Anatolia from Miocene onwards. This is evidenced by exposure and vent distribution of the central Anatolian volcanics confined to two major fault zones namely, the Central Anatolian Fault Zone (or Ecemis Fault Zone) and the Tuz Gölü Fault Zone. In a wider regional context, CAVP monogenetic basalts are comparable to Apuseni Mountains (Romania) and Big Pine (Basin and Range) volcanics, except CAVP basalts have depleted Ba contents. There is a need for systematic petrological study to expand the database and have a better picture of monogenetic volcanism within the CAVP.
In the Central Anatolian Crystalline Complex (CACC) the Late Cretaceous postcollisional granitic magmatism is followed by Eocene extension, resulting in formation of roughly E-W trending transtensional basins. The volcanic rocks, mainly submarine lava flows and subareal domes are concentrated along these Middle Eocene (Bartonian) basins. The volcanic rocks are basic to intermediate and are classified as basalt, basaltic andesite and rarely alkali basalt and trachy-andesite. Petrographically they are generally plagioclase + pyroxene ± olivine ± hornblende ± biotite pyhric, indicating a shallow crystallization level. They are characterized by several disequilibrium textures, which may suggest role of magma mixing/mingling process during their evolution. Eocene volcanic rocks are characterized by high phenocryst contents, low but variable MgO concentrations (0.54-9.30 wt %), low Mg numbers (19.57-55.57) and low compatible trace element concentrations (Ni 5-166 ppm; Co 7-32 ppm), which provide strong evidence for the mafic mineral fractionation. Their relatively high Zr and Y contents provide strong evidence for their transitional to mildly alkaline nature and also point out their within-plate characters. All studied samples are strongly and variably LREE enriched relative to chondrite with the (La/Sm) N ratio of 2.26 - to 6.17 and show small negative Eu anomalies (Eu/Eu*=0.65-1.00), suggesting plagioclase fractionation. The REE patterns of the studied rocks are consistent with the derivation from a shallow depth (e.g. spinel lherzolitic source). They have negative Nb-Ta and Ti anomalies in the primitive mantle normalized diagram and are characterized by low Nb/La (0.21 to 0.62), Ce/Pb (3.70-34.90) and Nb/U ratios (1.11-30), which may indicate an interaction with the Late Cretaceous granitic host rocks in the course of their ascent.
The volcanic rocks display similar but variable ranges of Sr, Nd and Pb isotope ratios. εNd values range from 0.12 to 4.06, which is indicative of an isotopically depleted mantle source. They have relatively high and variable LILE/HFSE, LILE/LREE ratios (e.g. Ba/Nb 32-208 and Ba/La 16-46) and relatively radiogenic Sr, Pb isotope compositions (0.70404-0.70559 and 18.62-19.17 for 206Pb/204Pb 15.58 – 15.68 for 207Pb/204Pb and 38.65 – 39.00 for 208Pb/204Pb), indicating that they were derived from a heterogeneous lithospheric mantle that had been metasomatised by subduction related agents such as fluids and/or melts during a previous geodynamic event. On the other hand, high LILE and LRE contents of the rocks point out fluid dominated metasomatism rather than melt metasomatism.
Eocene volcanic rocks are supposed to be formed as a result of post-collisional lithospheric extension that followed the Late Cretaceous thickening of the Central Anatolian Crystalline continental crust, related to the closure of the Neotethyan Izmir-Ankara branch of Neotethys. Geochemistry and geotectonic setting point out that lithospheric delamination was the most likely mechanism to generate these calcalkaline to mildly alkaline volcanic rocks in the CACC.
The studied area belongs to the Rhodope Massif and is located approximately 1km north of town of Xanthi, where a plutonic body of mainly granodioritic composition and Oligocene age intrudes into marble. It is generally medium-grained, composed mainly of plagioclase, orthoclase, quartz, biotite and hornblende.
Three samples of the skarn formation were collected; two from the aureole near Xanthi (samples WXT1 and WXT2) and one from the aureole near Kimmeria (sample WXB1).Thin sections of the samples were prepared in order to determine their mineralogical and textural characteristics. Furthermore, X-ray powder diffraction (XRPD) study was performed using a Philips PW1710 diffractometer with Ni-filtered CuKa radiation. Representative quantity of the samples was treated chemically. In this way the organic matter, fine carbonates and iron oxides (COI) were removed. The abundance and semi-quantitative estimates of the mineral phases present was determined from the untreated samples, whereas the form of the wollastonite present along with its unit cell properties were established from the treated ones (31 lines each). Finally, chemical analyses of the wollastonite were carried out using a JEOL JSM-840A Scanning Electron Microscope (SEM) equipped with attached Energy Dispersive Spectrometer.
All the samples are in general of massive fabric, forming fibrous aggregates with no distinct spatial orientation. Samples WXT1 and WXT2 are coarser grained compared to WXB1. The samples from Xanthi reveal elongated crystals of wollastonite with fractures parallel to the secondary cleavage (001), mainly filled with fine micritic calcite. The sample from Kimmeria reveals finer and elongated crystals of wollastonite, as a sample being also richer in calcite in aggregate form.
The samples are mostly composed of wollastonite (73-80%), along with considerable amounts of calcite (3-13%). Andradite is found in considerable amounts (up to 18%) only in the samples from Xanthi, while quartz is present only in Kimmeria samples. Clinopyroxene is not always found, as well as feldspars. The COI amount is greater in Kimmeria samples, showing an increasing tendency with the calcite content present in the samples.
From the unit cell data obtained from the chemically treated samples it is shown that all the samples are of triclinic structure, being in general very close to the wollastonite nominal structure. These from Xanthi show generally a slightly lower (a) angle. The wollastonite from Kimmeria demonstrates a more complex chemical content, which does not affect its crystal structure. The mean chemical formula of wollastonite in sample WXT1 is (Ca5.895Mn0.100Fe0.017)Si5.994O18, in sample WXT2 is (Ca5.846Mn0.152)Si6.001O18 and in WXB1 is (Ca5.833Mn0.120Mg0.045)Si6.001O18. The wollastonite from Kimmeria incorporates Mg2+ in its structure, whereas wollastonite from Xanthi Fe2+. Both demonstrate substitution of Mn2+ for Ca2+. The absence of vesuvianite and plagioclase, along with the presence of clinopyroxene, garnet, minor calcite and traces of quartz, indicates 0.05<XCO2<0.2 and temperature range of approximately 650-700ºC at 3 Kbar (corresponding to 10-20 km depth). This also implies a volumetric H2O wollastonite ratio of greater than 7:1. The skarn formation was not the same around the granodiorite, with reaction CaCO3+SiO2↔CaSiO3+CO2 reaching almost completion to its western margin, rather than its northern one, possibly due to insufficient amount of time and the type of marble permeability. The magmatic fluids interacting with the marble wall rock were gradually depleted in silica content and subsequently enriched in Al, Fe and Mg, forming andradite garnet and clinopyroxene.
The presentation outlines results from four years of processing data from permanent GPS stations in Bulgaria and the Balkans. Data from eight stations from the HemusNET network, joint Greek and Bulgaria project, along with another 21 GPS permanent sites on the territory of Bulgaria and another 11 located in the Balkan Peninsula are included in the routine processing. Twelve EPN stations for defining the terrestrial and kinematic frames are included in the solution. The processing is making by the state-of-art GAMIT/GLOBK GNSS software developed in the Massachusetts Institute of Technology. Time series of the coordinates and horizontal velocities of the permanent stations are obtained by processing and analyzing more than three years of data. The obtained horizontal velocities of the stations and the strain rate are in good agreement with the tectonic model of the Eastern Mediterranean and are contribution to the kinematics in the East Mediterranean region.
The basement of the Rhodope Metamorphic Province comprises four groups of tectonic units forming the Lower, Middle, Upper and the Uppermost Allochthons which were emplaced onto each other during a protracted orogenic history from Late Jurassic to Eocene. The Lower Allochthon includes the Pangaion-Pirin Complex, and the Arda, Kardamos/Kesebir, and Byala Reka/Kechros units. The units consist of Variscan basement and, partly, a metasedimentary cover dominated by marble. The overlying Middle Allochthon comprises slivers of both oceanic and continental crust and, in addition, orthogneisses derived from Late Jurassic to Early Cretaceous arc granitoids. It includes, among others, the Kerdilion unit in the Serbo-Macedonian Massif and the Sidironero-Mesta, Starcevo, and Asenica units in the Western and Central Rhodopes. The Middle Allochthon was thrusted towards southwest over the Lower Allochthon during the Palaeogene along the Nestos Shear Zone. The Upper Allochthon crops out most extensively in the Eastern Rhodopes (Kimi Complex) and in the Serbo-Macedonian Massif (Vertiskos/Ograzhden unit). These units represent Variscan continental crust which was affected by HP and partly UHP metamorphism in the Jurassic to Early Cretaceous. The Uppermost Allochthon (not exposed in the Western and Central Rhodopes) consists of low-grade metamorphic (greenschist facies, locally blueschist facies) sedimentary and volcanic rocks, partly of oceanic affinity. It includes the Circum Rhodope Belt along the SW border of the Rhodope Metamorphic Province and the Mandrica greenschists in the Eastern Rhodopes.
The Rhodope Metamorphic Province includes, in addition to the Rhodope Mountains proper, also the Rila and Pirin Mountains and the Serbo-Macedonian Massif. These different massifs are separated by basins of Paleogene and Neogene age. The Rhodope Metamorphic Province in Bulgaria and Northern Greece has been affected by significant extensional tectonics since the Middle or Late Eocene. An important fault system active in the Eocene and Early Oligocene includes the Ribnovo Fault on the eastern side of the Mesta Basin in Bulgaria and the Vertiskos-Kerdilion Fault in Greece. Together with several minor normal fault relicts identified during our studies, these represent an originally west-southwestdipping, low-angle (at least at the end of faulting) normal fault with greenschist facies mylonites in the footwall and cataclasites along the fault plane, the Mesta-Kerdilion Detachment, exposed over ca. 150 km along strike and about 50 km parallel to the slip direction. The Mesta-Kerdilion Detachment system removed the Vertiskos-Ograzhden Unit from the top of the Sidironero-Mesta Unit. The along strike horizontal displacement amount was more or less constant. The Ribnovo, Vertiskos-Kerdilion, and Alikochov faults accommodated the collapse of a thickened orogenic wedge above the subduction zone in which the Apulian plate is retreating. In that sense, the Late Eocene Mesta-Kerdilion Detachment system corresponds to the onset of Aegean extension. During the intrusion of several plutons in the Pirin Mountains at ca. 32 Ma, the footwall of the fault was uplifted to form a large anticline parallel to fault strike, and the fault was offset by a system of antithetic, northeast-dipping normal faults along the northeastern flank of this anticline (Dobrotino and Breznica faults). The Mesta-Kerdilion Detachment was later, in the Miocene, again crosscut and offset by the southwest-dipping Strimon Valley Detachment which accommodated important, core-complex-like exhumation to the south, strongly diminishing and finally ceasing towards north. This rotational activity of the Strimon Valley Detachment represents the onset of the extension that led to opening of the Aegean Basin. The Mesta-Kerdilion Detachment can be viewed as a precursor of this, but with slightly different kinematics (i.e. not involving significant vertical-axis rotation) and separated in time from the following events by a phase of relative tectonic quiescence in the Late Oligocene.
The Kushla caldera is located in the East Rhodope massif, in the border area of Bulgaria and Greece. The volcanic activity is realized during the Early Oligocene in subaerial environment. Several volcanic stages are distinguished: pre-caldera – dacite-trachydacite, latite and trachyte; syncaldera – acid pyroclastic rocks (mostly ignimbrites), and post-caldera – elongated subvolcanic bodies and dykes of basaltic andesite and shoshonite. Different tendencies of magmatic evolution are found which is probably related to magma differentiation in comparatively isolated core chambers that are settled at different level. Despite the fractional crystallization as the main process of magmatic differentiation for the separate tendencies, the processes of contamination and mixing are also important. Тhe mixing is probably the triggering mechanism for the acid ignimbrite caldera-forming eruption. The magmatic evolution of the volcanic rocks of the Kushla and Ostren Volcanic Subcomplexes is due to fractionation of plagioclase, sanidine and in less extent of hornblende, biotite and pyroxene as well as the fluid factor that controls the P2O5, К2О and Na2O. The magmatic differentiation of the Gorski izvor and Uchkaya shoshonite is related to the fractionation of pyroxene, plagioclase, olivine, magnetite and apatite. The lower pressure of the hornblende from the acid pyroclastics of the Ostren Volcanic Subcomplex (1.4-1.9 kbar) supports the idea for the presence of shallow magmatic chamber after which empting the main caldera-forming eruption is realized. The pressure of the Chatalalmdere Volcanic Subcomplex is comparatively higher (2.2–2.6 kbar) which is in accordance with the later eruption of deeper levels of the same chamber.
In September 2005 Geophysical Institute of Bulgarian Academy of Sciences after procurement procedure selected the Refraction Technology, Inc. to upgrade the existing National Operative System for Seismological Information (NOTSSI) to a modern digital seismological network. At the beginning of December 2005 all the equipment supplied were installed on seismological stations and acquisition and processing software was operating in the data center. The network became operational on 08.12.2005. The Bulgarian Seismological Network was equipped with broad-band sensors and digital acquisition systems. It enabled application of modern techniques of analysis of the velocity structure in Bulgaria. This study presents one of the first results from application of the receiver function technique. The Receiver functions were computed using scripts written on Seismic Handler program by Sodoudi F. The Western part of Bulgaria is characterized by mountains, river valleys and small fields between the mountains. Two stations of the network Musomishte (MMB) and Krupnik (KKB) were chosen in south-west of Bulgaria and also station Vitosha (VTS) which is close to Sofia and known as the station with lowest noise. These sites are located in areas of complex tectonic structures manifesting high seismic activity during recent years. As starting models we used shear wave velocity models for the territory of Bulgaria, obtained in Raykova R, 2004. For the study were used earthquakes in epicentral range 35 - 90o and with a magnitude more than 5,5 – 6 also with clear P-onset. All earthquakes from the end of 2005 to the summer of 2009 were used and a good azimutal covering was reached. From the seismic survey and gravimetric measurements is determined a Moho depth between 30 km and 50 km. The crust is shallower in the north-eastern part of the country and thicker in the south-western part. The obtained results show ticker crust than expected Earth crust. This can be an effect of reflections/refractions on the object close to the station. They show only the main trends of the Moho depth for the whole country but not local effects in some part, beneath the mountains for example. Further detailization of the structure of the Moho boundary could be done after estimation of receiver functions for other stations of the network. The results show also very good the faults close to stations KKB and VTS.
Metabasic rocks in the Chepelare area occur in two different tectonic settings. Lences of garnet amphibolites are part of Chepelare mélange embedded in migmatic gneisses of Arda 1 tectonic unit. They reach length up to 15 m and in the variegated complex closely associate whit garnet-kyanite schists, impure marbles and granitoid migmatic gneisses. Whereas numerous small bodies of retrogressed eclogites trace out the ductile shear zone between Arda 1 and Arda 2 tectonic units.
Garnet, amphibole, plagioclase, ± diopside, ± quartz constitute the main minerals in garnet amphibolites from the Chepelare mélange. Accessory minerals are rutile, titanite, ilmenite ± apatite. Garnet occurs as lobate and resorbed porphyroblasts, up to 5 mm in diameter, containing inclusions of amphibole, plagioclase, epidote, quartz, titanite and abundant rutile. Many porphyroblasts have overcrowded by undistinguishable small inclusions core, often surrounded by inclusion-free rim. In finegrained samples garnets rarely include amphibole or quartz. It is almandine-rich (Alm 41-58, Grs 23-34, Pyr 18-30, Sps 1-3 mol%) with weak prograde zonation and almost lacking retrograde alternation to the rim. Porphyroblastic garnet is commonly surrounded by corona-like symplectites of sodic plagioclase (An27-30) and pargasitic amphibole, indicating retrograde metamorphic reactions at expense of garnet and omphacitic clinopyroxene. Amphibole inclusions in garnet have higher Al and Ti content and are mainly tschermakites. In some samples pseudomorph replacement of amphibole by K-feldspar, chlorite and andesitic plagioclase close to garnet porphyroblasts suggests further decompression reactions at active fluid regime. Pale green diopsidic clinopyroxene (Na2O = 0.7-2 wt%) in the matrix associates with oligoclase and is partly resorbed and enveloped by amphibole. In samples where abundant leucocratic material is present and close to almost completely resorbed garnet it includes unoriented small idiomorphic amphiboles. Incomplete replacement of rutile by ilmenite and titanite in matrix reflects the decompression path. The assemblage without the presence of Opx should reflect metamorphism in the HP granulite facies.
P-T estimates using Fe-Mg exchange equilibrium between garnet and clinopyroxene or amphibole and Al-in-amphibole and Grt-Hbl-Pl barometers indicate that the amphibolites reached at least pressures of 12-14 kbars and temperatures of 700-750°C for garnet inclusions and 750-800°C for the matrix assemblage. These new P-T data are consistent with previously reported for the garnet-kyanite gneisses from the Chepelare mélange.
Preliminary major and trace elements geochemistry plotted on discrimination diagrams suggests MORB affinity for the studied garnet amphibolites. Enrichment in Zr, Y, Nb, Ta, TiO2, LREE and more pronounced Eu anomaly of two samples from the southernmost outcrops do not precludes the possibility of incorporation in Chepelare mélange of metabasics with different protoliths or stronger interaction with the host migmatic gneisses of granite composition. The later is supported also by high variability in LREE patterns. Additional geochemical studies are planned to reveal the possible connection with retrogressed eclogites from the ductile shear zone to the north, which according to the previous publications also show MORB-type geochemistry.
Petrological observations and P-T data support the metamorphism at least in HP granulite facies for the rock of variegated complex. We do not refer these new estimations as peak metamorphic conditions, as the HP/UHP metamorphic records could be completely erased by observed late high-temperature metamorphic overprint involving hydration reactions during the exhumation.
Acknowledgements: This study was supported by National Science Fund - Bulgaria, VU-NZ- 05/ 2005, DO02-363/2008.
In the last few years, a consensus has emerged according to which the Rhodope Metamorphic Complex (RMC) has started undergoing post-orogenic extension in the early Late Eocene or before. Hence, no significant compressional structure younger than the Middle Eocene should be observed in it. In the Bulgarian Central Rhodope, the lower part of the metamorphic pile is mostly made of migmatitic orthogneisses from which several zircon and monazite U-Pb ages around 36-37 Ma have been reported. This may suggest that the structures formed during migmatization and subsequent cooling of this part of the dominating in the literature.
Our analysis in the area of Chepelare documents the following. The metamorphic rocks are exposed as a ~5 km-thick north-dipping monocline defined by foliations and lithological contours. In the largest part of this pile, structures consistently document top-to-SW shearing developed during and subsequent to anatexis. The middle part of the section shows a more variegated rock assemblage that coincides with a ~1 km-thick zone of intense strain here termed the ‘Chepelare Shear Zone’ (CSZ). The CSZ has previously been interpreted as a synmetamorphic thrust of presumed Mesozoic age. From a strongly sheared synfolial pegmatite sampled within the CSZ, we obtained a monazite U-Pb age of 36.3 ± 0.4 Ma (weighted mean age upon 16 analyses) and a muscovite 39Ar/40Ar single-grain plateau age of 34.9 ± 0.2 Ma. These results are consistent with published ages for the broader area and indicate that the CSZ was active during the time interval from 36 to 35 Ma (at least). Higher levels of the monocline, above the CSZ, show a domain of less severe strain and lacking pronounced stretching lineations, then a domain of higher strain that includes ~1-3 m-thick shear zones with low dips toward the north. The shear zones bear N-S-trending stretching lineations and display top-to-N shear criteria. Some of them are underlined by a synkinematic pegmatitic or granitic vein running along their axis. The top of the monocline is defined by a north-dipping fault zone (with ultramylonitic marbles and thick cataclasites) that also displays top-to-N shear criteria. This well known low-dipping fault zone, initially described as a thrust, has later been reinterpreted as an extensional detachment. Together with the domain of top-to- N ductile shearing in its footwall, we refer to this fault zone as the ‘Mihalkovo-Drianovo Shear Zone’ (MDSZ). Within the MDSZ, from one shear zone bearing a syn-kinematic pegmatitic vein, we obtained a monazite U-Pb age of 38.0 ± 0.1 Ma (weighted mean age upon 58 analyses) and two muscovite 39Ar/40Ar single-grain plateau ages of 34.2 ± 1.2 Ma (large flake) and 32.3 ± 1.2 Ma (recrystallized flake). From another shear zone, we obtained two muscovite 39Ar/40Ar single-grain plateau ages of 34.4 ± 0.2 Ma (granitic vein) and 34.4 ± 0.4 Ma (host gneiss). These results indicate that the MDSZ was active during the time interval from 38 to 34 Ma (at least).
As a consequence, the MDSZ and the CSZ were synchronously active, at least during the period from 36 to 35 Ma. Because the two shear zones have opposite kinematics but fairly identical dips (the difference is 10° at most), this synchronism implies that one of them was initially a thrust and the other was normal-sense, whatever the amount of tilting the metamorphic pile may have undergone subsequently. Of the two solutions left, the one where the underlying CSZ was a thrust and the overlying MDSZ was normal-sense is, by far, the most likely. Consequently, our study documents synmetamorphic thrusting in the Bulgarian Central Rhodope during the Late Eocene. This is consistent with the picture arising from the Nestos Shear Zone, in Greece, and confirms that the onset of post-orogenic extension in the RMC occurred in post-Eocene times. In addition, syn-orogenic extension, so far suspected, is now well established and appears to have developed within the RMC while it was the hot core of the Alpine orogen.
An overview of the UV activities in Belgium is presented including the balloon borne, Space borne and ground based measurements (at 5 stations) of the global and direct Solar irradiance. Main results in terms of biologically active UV are discussed in relationship with the main factors of influence as Ozone, Clouds and Aerosols. Positive UV effective doses trend (+0.6 % /Year) is discussed in correlation with the ozone negative trend (-0.2 % /year) and more favorable meteorological conditions. Finally, some information is on the future activities namely, the UV indices predictions in real conditions.
Bogdanas river flows east of Thessaloniki in Northern Greece. Its sources are found at the western part of the Vertiskos mountain and flows along the Assiros and Lagada plane towards Koronia lake. In this study, variations of the heavy metal concentrations in Bogdanas river sediments have been evaluated. Sediment samples were collected at 8 representative sampling sites along the river, during two sampling periods. Chemical analysis indicated that the sediment samples show variable concentrations of heavy metals. Sediment quality assessment according to the limits determined by the European Community’s legislation indicated that the river sediments were not contaminated, apart from 3 samples and 1 sample concerning Zn and Cu, respectively. On the other hand, sediment quality assessment according to the US EPA Sediment Quality Guidelines (SQG) revealed that there was heavy metal pollution with respect to especially Zn, Cu and Ni. Concerning Zn, only 1 sample is close to the EPA’s moderately polluted level, while 10 samples surpass it and 5 samples exceed the EPA’s heavily polluted level. Concerning Cu, 7 samples are classified as moderately polluted and 9 samples as heavily polluted. Finally, no pollution is defined for Ni, apart from 2 samples which are classified as moderately polluted. In conclusion, the research showed that the revealed heavy metal pollution is more attributed to the lithology of the area and less to human activity.
The Mygdonia basin is considered to be of a rather moderate seismicity rate area, with strong earthquakes occasionally occurring and affecting the northern Greek mainland. It corresponds to a complicated extensional setting bounded from normal faults that reveal a characteristic S – shape development. According to previous studies, the central part of the basin which mainly consists of faults trending E – W, are active structures that played a basic role in the formation of the basin. Both active faults and earthquakes appear in populations, characterized by certain spatial properties. A composite examination is attempted in order to investigate both earthquake and fault population properties taking into account all the available information that can be extracted from the correlation of seismicity and topographic data of the broader Mygdonia domain. It is known that the establishment of a dense seismological network contributes to the detailed analysis of the majority of the active structures since the distribution of the earthquake foci reveal the presence and particular properties of the active seismogenic zones. All earthquakes with magnitude M ≥ 1.0 which were recorded during the time period 2007 to 2009 from the National Greek Seismological Network are thoroughly examined. For this reason, arrival times of well recorded events that occurred in the basin were taken into account. The Wadati method was applied, to compute the Vp/Vs ratio and the origin times of the earthquakes with adequate data. Using the origin times derived from the best fitting data, travel times of the P waves were constructed to define the crustal structure in the area. In addition, time residuals were calculated in order to take into account the lateral variations of velocities. According to the results, all earthquakes that occurred in the area were relocated and their focal properties were determined again. Hypocentre determination was improved with the use of the VELEST algorithm. Cross sections perpendicular to the fault zones were plotted in order to approximate their depth. It is also known that innovative advanced tools lately applied in geosciences, provide a versatile approach in studying active fault systems. For this reason, high quality topographic maps along with any available tectonic data regarding active faulting were also used in order to investigate the properties of the faults population that dominates in the study area. Fault outcrops with a wide range of sizes are depicted as tectonic lineaments and GIS methodology is used for their analysis. Accurate digital elevation models (DEMs) of the area were constructed, while, cross sections and topographic profiles were produced mainly where seismicity is clustered. Similarities extracted from both methods, give combined interpretation about the fault possible segmentation or linkage either at the surface or at depth. The combined results from such an investigation provide important contribution to fault interaction, fault segmentation, seismotectonic zoning and seismic hazard assessment.
Numerous magmatic intrusions follow the Inner-Carpathian calc-alkaline volcanic arc with decreasing age towards the East-Southeast. At the West Carpathians intrusions located: in south-eastern Moravia (internal Biele Karpaty nappe of the Magura flysch unit); and in the Pieniny Mts. between the Magura flysch unit and the Pieniny Klippen Belt. At the internal East Carpathians a big volume subvolcanic body (Ţibleş-Toroiaga-Rodna-Bârgǎu) found between the Gutâi and the Cǎlimani volcanic massifs.
The Moravian high-K pyroxene-amphibole basalt and andesite intrusions extend southeast of the Morava River. They are sills, dykes and irregular bodies. Emplacement of intrusions was post-tectonic, and the intrusive rocks have been generally affected by postmagmatic alteration. Towards the east at the Slovakian/Polish border, products of intrusive activity form approximately a 20 km long belt of the Pieniny Andesite Line. It post-dates the Early Miocene folding and strike-slip movements. The magma made its way along tensional fissures that opened above a steeply bent downgoing North European Plate. Emplacement of intrusions took place in two phases: 1st phase intrusions are mostly dykes, parallel with the strike slip fault at the northern part of the Pieniny Klippen Belt; the 2nd phase intrusions are restricted to the westernmost part of the Pieniny Andesite Line and follow transversal faults that cut the 1st phase andesites. The Toroiaga intrusive area situated north of the Rodna Mts., consist of a complex subvolcanic intrusions with pierce metamorphic rocks and its southern part, Paleogene to Miocene sedimentary deposits, suggesting a multiphase intrusive activity. Hydrothermal activity and mineralisation processes are related to the 2nd and 3rd phase intrusions.
Major and trace element chemistry of the examined intrusive rocks are indicating subduction-related magmas. Compared to the Pieniny intrusives, the Moravian and the Toroiaga intrusive rocks are relatively enriched in potassium, sodium and other incompatible elements. These latest are lying at the boundary of high-K calc-alkaline- and shoshonitic suites. The LILE enrichment reflects the contribution from the subducted slab, at least the parental magma derived from metasomatised subcontinental lithospheric mantle. Source composition and partial melting was more important then the FC, AFC processes and/or crustal contamination. Partial melting process was triggered by the flux of heat coming from the rising asthenospheric material once the delamination of the subducting European Plate occurred