PECULIARITIES OF LITHOGENESIS AND OIL AND GAS PROSPECTS OF PALEOCENE DEPOSITS OF THE NORTHERN SLOPE OF THE KARKINITsky THROUGH

Abstract

The results of complex lithogenetic studies of Paleocene sediments of the northern side of the Karkinitsky Through are presented. Lateral lithological-litmological and facial variability of Paleocene deposits is characterized, which is manifested both in the whole section of the Paleocene and its individual epochs. In general, in the deposits of the Danish and Zealand epochs in the western and eastern parts of the territory, thick bodies of limestone litmites have been developed, which are overlapped by clay formations of the Tanetiant age. The central part is dominated by marl litmites. It is shown that bioherm formations located in the Golitsyno-Schmidt and Bezymenny areas are replaced by plumes of destruction and depressive deposits of the outer shelf in the direction of the Flangova structure and pelagic part of the basin. A model is substantiated (from the beginning to the end of the Paleocene) of migration of the zone of bioherm formation in the northern direction, which was caused by a general rise (with some fluctuations) in ocean level. The model expands to some extent the range of localization of promising areas of potential reservoir rocks. It is determined that the formation of natural reservoirs occurred under the influence of processes of recrystallization of the bulk of rocks and organogenic remains, dolomitization, silicification, cavern- and fissure formation. Based on the reconstruction of regional processes of generation, migration, and accumulation, it is shown that the inflow of hydrocarbon fluids that formed the Golitsyn field occurred through the area of the Schmidt structure from the eastern part of the generation center (Cretaceous deposits of the Michaivska depression). A model of the lithophysical structure of Paleocene sediments along the profile of wells: Bezimenna-2—Flangova-2—Golitsyna-2— Golitsyna-3—Schmidta-6. Four promising objects (traps of arch type, lithologically constrained type and tectonically constrained types) were identified.