A comprehensive approach to clarifying the geological structure of reservoirs and the phase state of hydrocarbons within them using the example of the oil and gas condensate field of the Purovsky district in the Yamalo-Nenets autonomous region

UDK: 551.7.02

DOI: 10.24887/0028-2448-2026-6-18-22

Key words: phase state, geological model, oil and gas reserves, testing the reservoirs on a cable, nuclear magnetic logging

Authors: Yu.A. Rozhitsin (RN-GRD LLC, RF, Tyumen); D.N. Gubinsky (RN-GRD LLC, RF, Tyumen); K.F. Miropoltsev (RN-GRD LLC, RF, Tyumen); A.A. Latyntseva (RN-GRD LLC, RF, Tyumen)

Within the framework of this study, using the example of a unique oil and gas condensate field located in the Purovsky district of the Yamalo-Nenets autonomous region, the issues of clarifying the complex geological structure of the BU16(1-3) formation, characterized by the presence of an oil fringe, are considered in detail and resolved. A comprehensive multifactorial analysis was carried out, combining the study of core material, the interpretation of geophysical well logging data, the study of up-to-date field information, as well as the use of re-processed seismic data. As a result of the conducted research, the lenticular concept of the formation structure was substantiated and established, which significantly changes the idea of its structure. Special attention is paid to the analysis of seismic cubes of elastic properties and the construction of attribute maps of dynamic parameters. This approach enabled to prove the existence of two isolated deposits instead of the previously assumed single one. The key result of the work done was the revision of the phase state of hydrocarbon reserves: one of the identified deposits was transferred from the oil category to the gas-oil category. This clarification led to a significant increase in gas reserves and justified the need to transfer part of the oil reserves to the category of hard-to-recover ones. The developed and refined geological model enabled to substantiate a new, more rational strategy for reservoir development aimed at significantly increasing its geological and economic efficiency.

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