Construction of a tectonic model of the subsalt complex on the northwestern flank of the Precaspian syneclise, based on 2D MCS data for further assessment of oil and gas potential

UDK: 550.8.072

DOI: 10.24887/0028-2448-2025-8-22-26

Key words: Mugodzhar, Aktobe Pre-Urals, Pre-Urals Foredeep, Precaspian Basin, Ilek Step, geological exploration, seismic exploration, regional studies, oil and gas potential assessment

Authors: A.D. Eliseev (Gubkin University, RF, Moscow)

This article presents an analysis of the geological structure and development features of carbonate and terrigenous deposits in the junction zone of the Volga-Ural anteclise, the Pre-Urals foredeep, and the Precaspian basin. The analysis was carried out using available data in the fields of sedimentology, petrophysics, structural geology, tectonics, geochemistry, field development, and seismic exploration. Data were collected and, in accordance with regulations, digital and analog geophysical data, stored in the Republican Geological Information Center Kazgeoinform and/or Territorial Geological Information Funds. The quality and reliability of the source data were verified; interpretation of regional seismic survey data was performed; the results of structural and tectonic zoning were summarized; the boundaries of the Novoalekseevsky trough were refined for further assessment of the oil and gas potential of terrigenous and carbonate deposits of different ages in the subsalt complex of the sedimentary cover. Top and bottom maps of the salt complex were constructed, and a structure validity analysis was conducted with an assessment of the impact of velocity anomalies from salt diapirs on the underlying deposits. The results of this work will be used in further research aimed at locating exploration targets in Pre-Artian oil and gas prospective deposits. Future work will include analyzing the distribution of reservoir and sealing properties in the molasse deposit zone, as well as studying linear tectonic structures of the Pre-Urals foredeep and the localization of carbonate buildups.

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