Source rocks of the West Taimyr potential oil and gas bearing area according to drilling data

Introduction. The article discusses the results of geochemical studies based on the results of drilling the well on Leskinsky license area, which became the basis for revising the prospects for the oil and gas potential of the region within the perimeter of the Gazprom-neft LLC projects.
The purpose of this work is to generalize the Paleozoic petroleum system regional data of the West Taimyr potential oil and gas bearing area of the Enisey-Khatanga oil and gas bearing region.
Materials and methods. According to the results of exploration drilling, a Paleozoic series were discovered up to the Middle Ordovician deposits. The source rocks of the Permian, Devonian and Silurian ages are characterized. Permian source rocks of III type and the previously unstudied Ust-Enisey formation (S1 ue) containing the organic matter of I-II type from graptolitic shales of the Llandoverian and Wenlock series of the Lower Silurian have been confirmed. Upper Devonian source rock (Domba Formation D3 dm) identified earlier in West Taimyr outcrops has not been confirmed on Leskinsky license area.
Results. The obtained data about the properties of source rocks and the results of extracts analysis of the core and cuttings made it possible to significantly revise the conceptual model of the prospects for the oil and gas potential of the Paleozoic series on the territory of the West Taimyr potential oil and gas bearing area. The maturity of organic matter was evaluated, the main erosion events were studied for the presence of catagenetic unconformities, and the extract — source rock was correlated.
Conclusions. The data obtained made it possible to revise the prospects for the oil and gas content of the Paleozoic in such regions as the Lena-Tunguska, Enisey-Khatanga oil and gas bearing regions, and the Taimyr independent potential oil and gas bearing region.

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