Paleotectonic reconstructions based on CDP-3D seismic data: a case study of the South Torgai Basin

The article presents an innovative approach to interpreting tectonic faults under the complex strike-slip tectonic conditions of the South Turgay Sedimentary Basin based on high-density 3D seismic survey data. After processing, interpretation, and modeling using specialized algorithms, the obtained 3D seismic data provided objective information on the tectonic structure, genesis, and geodynamics of hydrocarbon exploration targets at one of the oil and gas fields in the Arysqum Depression. The field is represented by three structural highs, complicated by numerous tectonic faults, whose accurate identification has both scientific significance and practical applications for understanding the structure of hydrocarbon reservoirs. As a result of the conducted studies, it was possible not only to reconstruct the tectonic evolution of the field area during the formation of the target productive horizons in the Mesozoic and Cenozoic periods but also to offer a new perspective on the hydrocarbon potential of the preJurassic formations in the Arysqum Depression. Specifically, at the local level, the role of strike-slip tectonics in the formation of structural highs in the Mesozoic interval was confirmed. Additionally, assumptions were made regarding the presence of thrust faults in the Paleozoic interval, which explain the high lithological heterogeneity of the pre-Jurassic complex and suggest an expansion of the region’s hydrocarbon potential. The interpretation and reconstruction of regional paleotectonic settings, as well as the construction of fault models consistent with existing regional tectonic concepts, were somewhat complicated by the relatively small study area (~200 km²).