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The possibilities of Geothermy as a geophysical method are studied to solve forecast and prospecting problems of Petroleum Geology of the Arctic regions and the Paleozoic of Western Siberia. Deep heat flow of Yamal fields, whose oil and gas potential is associated with the Jurassic-Cretaceous formations, and the fields of Tomsk Region, whose geological section contents deposits in the Paleozoic, is studied. The method of paleotemperature modeling was used to calculate the heat flow density from the base of a sedimentary section (by solving the inverse problem of Geothermy). The schematization and mapping of the heat flow were performed, taking into account experimental determinations of the parameter. Besides, the correlation of heat flow features with the localization of deposits was revealed. The conceptual and factual basis of research includes the tectonosedimentary history of sedimentary cover, the Mesozoic-Cenozoic climatic temperature course and the history of cryogenic processes, as well as lithologic and stratigraphic description of the section, results of well testing, thermometry and vitrinite reflectivity data of 20 deep wells of Yamal and 37 wells of Ostanino group of fields of Tomsk region. It was stated that 80 % of known Yamal deposits correlate with anomalous features of the heat flow. Bovanenkovskoe and Arkticheskoe fields are located in positive anomaly zones. 75 % of fields of Ostanino group relate to anomalous features of the heat flow. It is shown that the fields, which are characterized by existence of commercial deposits in the Paleozoic, are associated with the bright gradient zone of the heat flow. The forecast of commercial inflows in the Paleozoic for Pindzhinskoe, Mirnoe and Rybalnoe fields is given. The correlation between the intensity of naftidogenesis and the lateral inhomogeneity of the deep heat flow is characterized as a probable fundamental pattern for Western Siberia.

The paper describes Lower Jurassic (horizons J16 and J15) and Achimovka (Neocomian clinoforms) reservoirs in the area of the Nyurol’ka megadepression and its framing (42,000 km2). The total thicknesses of seven Achimovka sedimentary cycles are mapped. The thermal history of the Togur and Bazhenov parental sediments in the sections of 39 deep wells is reconstructed by paleotemperature modeling. The geotemperature criterion is used to identify paleosources of oil generation, starting from the Jurassic. The distribution of the relative density of the resources of the generated Togur and Bazhenov oils is estimated and shown on sketch maps. The Lower Jurassic reservoir is divided into zones depending on the distribution of the relative density of the Togur oil resources, and the Achimovka reservoir, of the Bazhenov oil resources. The priority oil search zones are proposed.