One of the most important issues in petroleum geology is related to the processes of hydrocarbon generation and accumulation at great depths. The Caspian basin is one of the most promising objects in terms of oil and gas potential at great depths. To date, the processes of hydrocarbon formation in subsalt strata have been poorly studied in this region, but are of high interest. The generating rocks of the Caspian sea region are considered to be terrigenous, siliceous-carbonate deposits of Devonian-Carboniferous age and Permian carbonate- argillaceous deposits in the depth range from 4 to 5 km with sapropelic-humus type of organic matter.
The article considers the generation potential, determined using the Rock-Eval method, of the main generating strata in the Caspian basin - Devonian, Lower Carboniferous, Middle-Upper Сarboniferous, Lower Permian deposits. The core was studied from a well located on the Eastern side of the Caspian Basin, in the Aktobe region. In this area, such studies were conducted for the first time. The analysis of 15 rock samples was carried out by the Rock-Eval method with further interpretation. The position of most stratigraphic boundaries in the well could not be established reliably, so they were established conditionally based on geophysical data. As a result, oil and gas source rocks were identified in the section of the well characterized by II, II-III and III types of kerogens. Some of the samples in the well were immature. The article presents modified Van Crevelin diagrams, a graph of the dependence of the kerogen productivity index on Tmax, a graph of the dependence of the total organic carbon content (TOC) on the generation potential of the rock (S1+S2).
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