VOLUME 19 (2)/April 1989

St. Boyadjiev. Petrology of Pirin granitoids. On the basis of spatial relationships, petrological and structural studies, accessory-mineralogical, geochemical and paleogeophysical data, the following groups of plutons are distinguished in Pirin Mountain: Spančevo (of probable Late Proterozoic age), Bezbog (Southbulgarian type, Hercynian age) and young – Central Pirin (Central Pirin and Dautovo Kresna), South Pirin (Tešovo, Golešovo and Ljahovo) plutons of Middle Alpine, probably Laramide age. All plutons are of anatectic origin which is responsible for their analogous granitoid character granodiorites, dominantly granites, in parts leucogranites. They were formed as a result of discontinuous magma generation and this predestines a number of their specific features.
   The Alpine granitoid plutons, including the temporally associated dyke formation, show higher, above the klark content of W, Mo, Fe, Cu, Pb, Zn, As, Sb, Au, Ag. The young granitoid plutons form different in size skarn zones with repeatedly superimposed hydrothermal ore formations. The polystaged and polycomponent ore zones are perspective for prospecting for rare-metal-sheelite-bearing, Mo-greisen, polymetallic, arsenopyrite-pyrite, gold and other ore minealizations.

E. Kozhoukharova, M. Ichev. Dynarnornetamorphism and pseudofossil effects in marbles and calc-schists of Lukovica Formation in Asenovgrad area. The study is scoped on the character and mechanism of late (Alpine) transformations of the amphibolite facies Precambrian rocks of Lukovica Formation in Asenovgrad area. Their irregular development depends on structural and lithological factors. Marbles and calc-schists are most strongly affected and turned into mylonites which visually resemble carbonate sediments and the traces of deformational tectonoclasts remaind of macrofossil imprints. Intrafoliation movements are of dominant role and as a result formed numerous low-amplitude shear zones of intensive dynamometamorphic transformations at different stratigraphic levels. The zones are structural and compositional, of destructive and constructive effect: brittle and ductile deformations, granulation and diaphthoritic crystallization of new mineral paragenesises in greenschist facies.

No abstract is available for this article.