Examples of the clinoform-block structure of the Achimov deposits of Western Siberia, established on the basis of a comprehensive analysis of the results of detailed correlation of well sections and seismic studies

UDK: 550.83.05

DOI: 10.24887/0028-2448-2025-8-16-21

Key words: Achimov deposits, geological structure, clinoform, seismic studies, detailed correlation of well sections, synsedimentary faults

Authors: .S. Gutman (IPNE LLC, RF, Moscow); A.V. Shubina (State Comission on Mineral Resources, RF, Moscow); D.A. Urusova (IPNE LLC, RF, Moscow); E.S. Gaponenko (IPNE LLC, RF, Moscow)

A detailed study of the geological structure of any oil and gas-bearing object plays an important role in the geometrization of deposits. Often, to solve it, the authors rely only on seismic studies in the presence of a network of wells. The article presents examples when a detailed correlation of well sections in a certain part of a seismic section contradicts the results of 3D studies, which indicate the clinoform structure of the studied stratum. On two correlation schemes of well sections, in accordance with the direction of two deep seismic sections, the reference intervals of the section are traced, which coincide with the seismic survey results before the sedimentation fault. It should be noted that after the fault, where the clinoform fall of the seismic phases occurs, it is from this moment on that other types of section are recorded on the correlation diagrams, which ultimately determines the sharp discrepancy between the results of the correlation of the well sections. A similar pattern of clinoform fall of the reflecting horizon can be seen in the regional section within the Yarsomovsky trough and its western branch. Although no faults have been recorded in this section, their presence is beyond doubt, and what type of section is in the area of these deflections can actually be judged only from the data of the wells.

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