Prospects for the oil and gas potential of the sedimentary strata of the South Caspian Basin according to paleotectonic and geodynamic criteria

Abstract

In the article, based on the study of paleotectonic, paleotemperature properties of the evolution of the western and eastern semi-basins of the South Caspian depression (SCD) and of the local elevations that have developed there, we found that within the Absheron Ridge and Turkmen shelf, which make up the north-northeastern slope of the depression, compressive stresses played a key role in the formation of local elevations, development of faults and mud volcanism, and in their oil and gas potential. By using a number of paleoprofiles constructed based on the seismogeological profile running in a southwest-northeast direc- tion, as well as morphological specifics of the local elevations developed within both the Absheron Ridge and the Turkmen shelf, we plotted and analyzed isomorphic maps reflecting the properties of distribution of the compressive stresses. Based on the paleoanalysis, we determined that the isometric Janub elevation, neither morphologically nor genetically, can be included into the same anticline zone as the local elevations under consideration. Studies suggest that they have developed under different tectonic regimes and the Janub structure belongs to a group of folds formed under another tectonic regime, i.e. new predicted anticline zone. The Janub-2 elevation, located southeast of the Janub fold, can be attributed to the predicted new anticlinal zone. In order to trace the continuation of this anticline zone in the southeast direction and identify potentially promising new buried elevations, it is advisable to carry out new series of transverse deep seismic profiling works in the southwest-northeast direction. The analysis revealed that the oil and gas potential, folding and evolution of mud volcanism in the area under study are associated with geodynamic processes. The impact of compressive stresses, as a geodynamic factor, on folding and faulting of the sedimentary mantle, mud volcanism and oil and gas potential is a relevant topic to study. The main research objective was determining the directions of exploration works based on deeep structure, paleotectonic, geodynamic and paleotemperature evolution environment of the SCD.