Home – Home – Jornals – Russian Geology and Geophysics 2018 number Неопубликованное

For the first time, the geochemical features of the kerogen composition of the Jurassic deposits in the central and southeastern regions of Western Siberia have been studied in detail. The patterns of changes in the pyrolytic, isotopic, and elemental characteristics of organic matter (OM) have been established, and information has been obtained about its genetic type, maturity level, and oil and gas generation potential. The main oil-producing complexes of the Jurassic deposits are considered: the Bazhenov Formation, the Togur Formation in the Tomsk Region, the Danilovskaya Formation, the Verkhnemaryanovskaya Formation, and the Nizhnetutleymskaya Subformation in the Khanty-Mansi Autonomous Okrug (KhMAO), as well as the Georgievskaya Formation in the Tomsk Region and the KhMAO, which have the elemental and isotopic compositions of kerogens characteristic of mature aquagenic organic matter and have a relatively high oil-generating potential. The moderately transformed Jurassic strata of the central and southeastern regions of Western Siberia are located in the main oil-forming zone, while the higher-temperature Salym section is located in the gas-forming zone. A decrease in the values ​​of the main geochemical parameters of kerogens (H/C_at and HI) is observed from Upper Jurassic to Lower Jurassic deposits: with increasing maturity, kerogen, like coal, becomes enriched in carbon. The use of schematic maps of Jurassic deposit catagenesis and the geochemical properties of kerogen will significantly enhance our understanding of the oil and gas potential for the southern regions of Western Siberia.