Geological setting and hydrocarbon prospects of the lower permian subsalt succession within the Right-Bank sector of the Astrakhan gas condensate field

Background. The subsalt Lower Permian rocks in the southern Pre-Caspian Basin are recognized as a primary target for further hydrocarbon exploration (Voronin et al., 1991; Fedorova and Bystrova, 2010; Babasheva et al.; 2023; Merkulov et al.; 2023, 2024). Their considerable potential is evidenced by numerous oil and gas shows and commercial hydrocarbon inflows from the Lower Permian Filippovsky sediments, identified in wells within the Astrakhan Arch and adjacent areas of the Astrakhan-Kalmyk sector of the Pre-Caspian Basin. However, the development of this succession is complicated by active salt tectonics. Conventional seismic interpretation techniques are insufficient for resolving the internal structure of these formations or constructing reliable geological models. These challenges can be addressed through the application of full-volume seismic interpretation, one of the most advanced methods for constructing geological models of complex subsurface areas.

Aim. To construct a geological model of the Lower Permian subsalt deposits within the Right-Bank sector of the Astrakhan Gas Condensate Field (AGCF) and to evaluate their hydrocarbon potential using full-volume seismic interpretation technology.

Materials and methods. Geological modelling of the Pravoberezhny section of the AGCF was conducted based on the results of 3D common depth point seismic surveys covering 800 km², well log data on the study area, and published materials on the geological structure and development of the sedimentary cover in the southern Pre-Caspian Basin.

Results. A geological model of the Lower Permian subsalt deposits in the Pravoberezhny section of the AGCF was developed. Large anticline-type objects recommended for further study were identified.

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