Generation and emigration of hydrocarbons in the Meso-Cenozoic complex of the Black Sea-Caspian region

Abstract

As part of the assessment of the prospects for oil and gas potential in the study area, numerical modeling of generation and accumulation systems was performed, as a result of which the centers of hydrocarbon generation located within sedimentary basins were identified. Based on the levels of modern maturity and OM transformation of the established and proposed oil and gas source rocks, as well as the estimates of the specific densities of hydrocarbon emigration at 5 stratigraphic levels, independent generation centers were identified: Middle Jurassic, Lower Cretaceous, Eocene, Maikop and Miocene. Variations in the sinking rates of basins at different stages of their development had a critical impact on the realization of their generation potential by oil and gas source strata. As a result, source rocks of the same age in the basins overcame the critical moment at different times and by now have realized their potential to varying degrees. In basins with low subsidence rates, there is a delay in the emigration process with respect to generation, which is not typical for basins with high rates. The main promising complex within the study area is Cretaceous deposits, the hydrocarbon saturation of which is provided both by its own source rock and by flows from deeper horizons of the sedimentary cover. The second most important are the Paleogene complex. Keywords: Black Sea-Caspian region; Meso-Cenozoic complex; cata-genetic zoning; modern maturity of deposits; degree of transformation of organic matter; generation; emigration; critical mome.