The observed situation with the multivariance of existing concepts of the Pre-Caspian depression formation is due to the fact that today there is no information on the material composition of the basement rocks in the Central Pre-Caspian Depression. Data about them have been obtained only on the basis of indirect methods (seismic data and gravimetry), also contribute to the ambiguous interpretation of the results of geophysical studies and a small number of deep wells, which also do not add the necessary critical mass to understand the entire geodynamic evolutionary path that its deep subsoil has gone through.
When analyzing the main concepts currently existing, it was found that the processes of eclogitization of the earth's crust and rifting were noted as the leading factors responsible for the formation of the Caspian structure. As a result, the failure of the processes of the first group and the second (with a wide manifestation of the processes of formation of the oceanic type of crust) was revealed, the concepts were also cut off by the time criterion, i.e. considering the formation of the structure in the post-Cambrian time.
Despite the plurality of opinions and the lack of a common opinion on the nature of the Pre-Caspian depression foundation, caused by the above reasons, the authors attempted to revise existing views based on information received in recent years. A critical analysis of the available materials and published literature on this topic was carried out, which makes it possible to speak more constructively about the possible evolution of the geostructure.
There are three stages in the formation of the Pre-Caspian: subduction-collisional (Early Proterozoic), aulacogenous (Late Proterozoic), thermal-relaxation associated with plume subsidence, cooling and formation of the structure of the basin (Early Paleozoic).
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