| Summary: | The regions of the West Siberian oil and gas province have unique paleoclimatic features: 1) Mesozoic-Cenozoic secular course of temperature, individual for regional paleoclimatic zones; 2) different scale processes of formation and degradation of Neopleistocene permafrost sections; 3) zonal and periodically forming late Quaternary ice sheets. The purpose of research is to assess the influence of factors paleoclimate (secular temperature course on the earth's surface and Neopleistocene permafrost strata) on the calculated geothermal regime of parent oil-source suites that determines the calculation of the density of hydrocarbon resources by three-dimensional-genetic method. The object of research are the Bazhenov and Togur deposits of Mesozoic and Cenozoic section, stripped by deep wells in the south-east of Western Siberia (North Festival and Luginetskoye hydrocarbon deposits of Tomsk region).Research is based on the method paleotemperature simulation — solving the inverse and direct problems of unsteady geothermy under conditions of sedimentation on multivariance of paleotectonic and paleotemperature reconstructions, on conformity assessment of results reconstructions to the criteria of optimal solution of the inverse problems of geophysics and the degree of harmonization of rated centers of generation of oils with established oil and gas presence in the interior.The necessity to take into account Neopleistocene permafrost of about 300 meters thick and of the use of local (regional) secular progress of temperatures on the earth's surface for adequately recover of thermal history of parent oil source deposits on the lands of southeast Western Siberia has been established. In case of permafrost strata are neglected estimated hydrocarbon resources HR, determined by the volume-genetic method, can be underestimated up to 25—30 %. In the case of neglecting paleoclimatic temperatures running calculated HR can be underestimated from 50 % to 4 times lower.
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