DISTINGUISHING THE HAUTERIVIAN-BARREMIAN SEDIMENTS IN THE KARKINITSKO-NORTH-CRIMEAN THOUGH (ZAKHIDNO-ОKTYABRSKA AREA) BY MICROFOSILLS

According to bio-and lithological methods, we have identified and stratified Lower Cretaceous (Neocomian) deposits from well sections: № 29 and 31, which were drilled on the territory of the Zakhidno-Оktyabrska area of the Karkinitsko-North-Crimean though. Hauterivian deposits are found in the depth range 3131-3142 m (wells № 29-Zakhidno-Оktyabrska), in the depth range 3218-3228 m (wells № 31-Zakhidno-Оktyabrska) and Barremian deposits in the depth range 3105-3131 m (wells № 29-Zakhidno-Оktyabrska) and in the depth range 3196-3218 m (wells № 31-Zakhidno-Оktyabrska), which were previously dated to the Neocomian. We have supplemented the paleontological characteristics of dinocysts and spore-pollen complexes of the biozonal scheme of Lower Cretaceous sediments of the Plain Crimea, which is being developed in the Department of Stratigraphy and Paleontology of Mesozoic Sediments of the Institute of Geological Sciences of NAS of Ukraine within the budget theme “Biostratigraphy of Meso-Cenozoic deposits of oil and gas regions of Ukraine as a fundamental basic basis for the systematic support of geological works” 2022-2025. Based on the peculiarities of the lithological composition of the rocks and the palynological characteristics of the deposits of the Kalininska suite of the Lower Cretaceous deposits of the Crimean Plain, we suggest that the Mesozoic Commission of the NSC of Ukraine consider the issue of distinguishing within its scope two subsoils: the lower one, represented by gray, red-brown, fine-grained, clayey sandstones, sometimes with gravel, and the characterized the Hauterivian spore-pollen complex, and the upper one, represented by dark gray siltstones with layers of sandy or organogenic-detrital limestones, is characterized by the Barremian spore-pollen complex and dinocyst complex of the Odontochitina operculata zone, dated to the Barremian. This publication highlights the results of research conducted with the financial support of the Sepkoski Grant of the American Union of Paleontologists for research on “Stratification of Cretaceous deposits of the Karkininito-North Crimean though according to palynological data”, 2021 and partly under the budget program “Biostratigraphy of Meso-Cenozoic deposits of oil and gas regions of Ukraine as a fundamental basic basis for the systematic support of geological works”, 2022-2025.