Abstract: Hydrocarbon Generation History and Petroleum Potential of Sedimentary Basins on Northwestern Black Sea Shelf

LARCHENKOV, EVGENY

Reconstruction of hydrocarbon generation history during Late Mesozoic and Cenozoic has been made on the basis of analysis of evolution of the sedimentary basins and estimate of subsurface pateotemperatures using original approach which takes into account alteration of heat flow value and thermal conductivity of rocks evaluated as function of their density which increased by subsidence depending of rate of accumulation and duration of time after the end of sedimentation.

The calculation has shown recent temperatures within Cretaceous, Paleocene and Miocene sequences are maximal temperatures during all Meso-Cenozoic history of basins formation. On this basis spatial localization of oil generation window (OGW) throughout the time has been evaluated. Significant part of Lower Cretaceous unit has passed OGW; however, another of its part is on. Less than half of Upper Cretaceous unit is on OGW now, and only a small area in the deepest part of Karkinit depression is off. Not too much of Eocene rocks and small part of Majkop Series are in OGW

There are many structural and stratigraphic traps which are located both within OGW and close to them, and these traps appeared before the beginning of active hydrocarbon generation, a favorable factor for oil accumulation. However, now there are known ten commercial and non-commercial only gas and gas-condensate fields on the offshore, and three of them - Golitzyn, Shtormovoe and Schmidt - are developed.. Fields may include from one (e.g., Krimskoe and Shtormovoe) to four (Golitzhin) productive porous and fractured sandstone, limestone and marl reservoirs at depths from 500 m to 2190 m. There are 17 pools located in Miocene (1), Majkop Series (11), Eocene (1), and Lower Paleocene (4) units. Analysis of the basin evolution and oil generation history gives persuasive evidence of a real possibility for discovering oil fields on the NW Black Sea offshore.

AAPG Search and Discovery Article #90942©1997 AAPG International Conference and Exhibition, Vienna, Austria