The study of regional and semi-regional areas of “small grabens” (in the terminology of some researchers) discovered in the 60-80s of the 20th century in Bashkortostan, which are new oil accumulation zones, continues. The detailing of the structure of these zones is carried out using the latest modifications of seismic exploration CDP-2D and CDP-3D. Detailed studies are relevant due to the natural interest in further study of oil ccumulation zones, which are able to replenish the hydrocarbon resource base. The article considers the results of a detailed study of the structure of post-sedimentary troughs (PST) and adjacent territories, carried out at the site of the Kabakovskoye field, which is part of the block controlled by the Zagorsk PST. The analysis showed that the PST system is formed by 2-3 main troughs – the most extended and seismically expressed in amplitude and width, and the fragmentary and less seismically pronounced troughs that occur next to them are the result of the reaction of a rigid geomechanical medium to the tectonic faulting. It is concluded that the formation of the PST was mainly influenced by the phases of tectonic activation on the margin of the ancient platform, while the influence of the Ural orogenesis was largely leveled by the pre-Urals marginal trough, the formation of which was completed in the Permian. The Urals influenced the orientation of the deflections that is consistent with it. Detailed seismic survey of regional graben troughs (“small grabens”) in Bashkortostan, which represents a significant part of the southeastern margin of the East European Platform, continues using the latest modifications of CDP-3D seismic survey. It is expected that this study will help to improve the methodology of geological exploration and to discover new hydrocarbon reserves.
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