Известия Томского политехнического университета: Инжиниринг георесурсов (Mar 2018)
Paleoclimate factors of reconstructing thermal history of the petromaternal bazhenov suite of the arctic region in Western Siberia
Abstract
The relevance. The earth of the Arctic region of the West Siberian oil-and-gas province have the unique paleoclimate features causing the need to improve schemes and parameters of quantitative assessment of hydrocarbon resources by volume and genetic method based on paleoreconstruction of geotemperature mode of petromaternal deposits. The main aim of the research is to synthesize the known data on Mesozoic and Cainozoic climate of northern part of Western Siberia and to estimate the impact of paleoclimate factors - century course of temperatures of a terrestrial surface and the Neo-Pleistocene permafrost thickness - on the settlement geothermal mode of petromaternal suites, defining the calculation of resource density. Object: Bazhenov deposits of the Mesozoic and Cenozoic section, opened with deep well 11 at the Arctic area (Yamal Peninsula). Methods: system analysis and construction of the century course of paleoclimate parameters; paleotemperature modeling considering the parameters of sedimentation history and the history of thermal properties of sedimentary thickness. Results. The author has matched the geographical and geochronological coordination of data on the century course of temperatures on the Earth's surface and the power dynamics of Neo-Pleistocene permafrost of the northern paleoclimate zone of Western Siberia, defined the «arctic» century course of temperatures on the Earth's surface, since the Jurassic time, and the century course of capacities of frozen rocks in quaternary time. It was determined that neglect of the century course of temperatures and permafrost thicknesses does not allow the adequate recovery of thermal history of maternal deposits. It is recommended when determining hydrocarbon resources by the volumetric-genetic method on lands of the Arctic region of Western Siberia to apply the «arctic» century course of temperatures and to consider the dynamics of thickness of the 300-600 meters Neo-Pleistocene permafrost. Otherwise the calculated hydro carbon resources can be underestimated to 40 %.
