FACEBOOKScientific-research institute of oil and gas industry of the National Joint-Stock Company Naftogas of Ukraine, Vyshneve, Kyiv region, 8а Kyiv str.,
Shows of lithospheric plates collision in region of Eastern Carpathians
Pages:
pp. 220-221
Abstract:
Classical shows of lithospheric plate collision in Carpathian region are known in the backside of Ukrainian Folded Carpathians and Trans-Carpathian flexure. These shows are: 1. Presence of sima (ophiolites) fragments in allochthonous occurrence. These are the complexes of basalts, andesite-basalts, trachytes that showed during the Upper Triassic – Lower Cretaceous. Fragments of ophiolites are known in the base of the Trans-Carpathian flexure, Marmarosh cliff zone and in the band of the thrust of Rakhiv-Burkut zone over the Krosno-Chornogora zone, as well as in the frontal part of the Marmarosh crystalline massif. 2. Post-orogenic magmatism is pronounced by Vygorlat-Gutynsk volcanic chain composed of basaltic andesites (70%), basalts (20-25%) and acidic differentiates (2-6%). Volcanic ridge stretches along the Trans-Carpathian flexure from the border with Slovakia to the town of Khust, where its strike changes to meridional and continues on the territory of Romania. 3. Increased heat flow in Trans-Carpathian flexure (more than 2 mkcal/cm2/sec) in comparison with 1,2-1,6 mkcal/cm2/sec in Folded Carpathians; - considerable emergence of Moho border up to 25-30 km in Trans-Carpathian flexure in comparison with 55-65 km near Folded Carpathians and Carpathian foredeep. In Trans-Carpathian flexure the heat flow sharply increases to over 2 mkcal/cm2/sec. Such values are characteristic to the Slovakian, Pannonian and Transilvanian depressions. 4. Variety of fluid shows on Carpathian border and in Trans-Carpathian flexure (gas fields, shows of oil, big amount of mineral water springs). In Trans-Carpathian flexure during the last time 5 gas fields have been discovered: Rusko-Komarivske, Stanivske, Solotvynske, Korolivske, Dibrovske and one carbon dioxide field (Martivske). Oil shows have been observed in salt mines near the towns of Solotvyno and Khust and in 6 wells at prospects of Solotvyno, Nonkove, Makarove etc. 5. Presence of gravity markers of collision area by which in Trans-Carpathian flexure is clearly fixed Maximum connected with marginal swell of Eurasian plate, Minimum connected with deepsea gutter and again Maximum connected with plate plunge in flat area of subduction under Pannonian microplate. 6. Presence in Badenian and Sarmatian deposits of Trans-Carpathians flexure intrusion - granite-diorite-porphyries. 7. Ore mineralizations (basemetal and gold deposits): Biganske basemetal and Muzhyivske gold field in the zone of Beregiv horsts, as well as Saulyak gold field in the Marmarosh crystalline massif. 8. Thrust and fold structure of Carpathians. Presently the thrust and fold structure of Carpathians raises no doubts of the investigators. The Moho boundary shows a significant uplift (to 25-30 km) in Trans-Carpathian flexure comparing to its subsidence (to 55-65 km) below the Folded Carpathians and Carpathian foredeep along the line Beregove-Dolyna-Vyshnevets. The corresponding values are along the line Chop-Sambir-Gorohiv – 28-32 km in Trans-Carpathian flexure comparing to 55-65 km in the folded part of the Carpathians and Carpathian foredeep. The above-stated indicates that in Trans-Carpathian flexure there is collision and flat subduction of Eurasian plate under Pannonian microplate.
