А conceptual model for the formation of oil and gas accumulation zone within the Paleozoic basement of the southeastern West Siberian basin

Abstract

In modern conditions of high demand for oil reserves in the Russian Federation, the most important region for its production remains the West Siberian oil and gas basin with target objects in well studied and developed Jurassic and Cretaceous sediments. The high degree of depletion of oil reserves at traditional sites and low exploration of complex and unconventional oil accumulations contribute to intensification of prospecting activities in Achimov, Bazhenov and Tyumen deposits, as well as those in deeper and less studied Lower Jurassic, Triassic and Paleozoic deposits located in the basement of sedimentary cover. The issue of oil and gas content of the pre-Jurassic complex of the West Siberian oil and gas basin has been debated for many years by experts, who highly appreciate the potential of identifying new large-scale oil and gas accumulations in such sediments. A series of recent discoveries in the Tomsk region (Urman-Archinsk group) confirms the importance of selecting such an exploration area. A review of existing ideas about the prospects of oil and gas content in the Paleozoic basement of the southeastern part of the West Siberian basin, along with an analysis of the identified conditions of hydrocarbon accumulation formation, allowed to propose a conceptual model that can be used as a basis for prediction when searching for accumulations in the pre-Jurassic complex.