Stages of sedimentation process in the Meso-Cenozoic complex of the South Caspian basin

The article reflects the latest studies of sedimentation processes during the geological period in the Meso-Cenozoic complex of the South Caspian basin. Based on the results of these studies, unlike previous studies, the sedimentary cover of the region is divided into several structural-formational complex floors: Pliocene-Anthropogenic, Miocene-Oligocene, Paleogene and Upper Cretaceous formations, and on the other hand, according to both seismic exploration and drilling data, regional profiles, starting from the Paleozoic are divided into 14 seismostratigraphic complexes (SSC) throughout the geological section up to the fourth period. One of the results of the research presented in the article is that the main source of hydrocarbon formation in the South Caspian Sea are rocks of Oligocene, Miocene, Jurassic age, they have a high potential for oil production, and it has been proven that a significant amount (10–15 % of OM is collected in these complexes). The activity of mud volcanoes in this area also confirms that the complexes are a source of hydrocarbon generation. It is known that mud volcanoes are closely related to the formation of hydrocarbons. One of the main geological factors that determine the rich oil and gas potential of the complex is the rate of accumulation of sediments and their elements. It is shown that the stratigraphic division of this complex is divided into 4 megastratigraphic sedimentary complexes. Within these stratigraphic complexes, the rates and volumes of sedimentation processes in different geological periods and epochs differed from each other. The article shows that the period of formation of the Lower Pliocene complex – the productive strata formed during 1.75–2.0 million years, and given its average rate of sedimentation was 2.5–3.0 km/million years, it can be concluded that among the world’s oil and gas basins has no analogue. This situation is associated with the peculiarities of the geodynamic and paleotectonic development of the South Caspian.