Klyushyna G. Lythology and facies features of Oligocene deposits of the north-western shelf of the Black sea

The results of the detailed lithological research of Oligocene sediments of north-western shelf of the Black sea on a complex methodical basis are represented in the manuscript. Lithological-genetic classification of Oligocene rocks have been developed, regularities of their distribution and conditions of formation have been determined. Mineralogical composition, morphological and structural features of detrital, clayey and authigenic components have been identified. By results of the investigations of authigenic minerals, physical-chemical and hydrodynamic conditions of sedimentation, and also main stages of diagenetic transformation have been determined. The types of lithological facies have been defined and schemes of their spatial distribution for the proper stratigraphic subdivisions of Oligocene have been constructed. Structural-facies zoning is conducted. The stages of development and sedimentation conditions of precipitation in Oligocene basin - planorbell, molochansk, kerleutsk (ryupel-chattian) time have been described. Key words: the Black Sea, north-western shelf, Oligocene, material composition, lithofacies, sedimentation.