Sergo Ordzhonikidze Russian State University for Geological Prospecting (Moscow, Russia)¹ ; Ministry of Science and Education of the Republic of Azerbaijan, Institute of Oil and Gas (Baku, Azerbaijan)²

Kerimov V. Yu., Head of Department¹, Leading Researcher², Doctor of Geological Sciences, kerimovvy@mgri.ru

Sergo Ordzhonikidze Russian State University for Geological Prospecting (Moscow, Russia)
Vyatkina E. V., Lecturer

Ministry of Science and Education of the Republic of Azerbaijan, Institute of Oil and Gas (Baku, Azerbaijan)

Gurbanov V. Sh., Chief Operating Officer, Professor, Doctor of Geological Sciences

National University of Science and Technology MISIS (Moscow, Russia)
Korotchenya I. S., Candidate for a Master’s Degree

The study presents research findings to prove the shale nature of the Diatom suite, the Maikop series and the Eocene deposits of the South Caspian Basin, which are characterized as hybrid systems exhibiting both hydrocarbon generation and accumulation properties. The criteria used for predicting shale hydrocarbon accumulations include: the transformation ratio (TR) indicating maturity of source rocks, geothermal regime, abnormally high pore pressure (AHPP) and reservoir pressure (AHRP), porosity, and specific densities of adsorbed and free hydrocarbons, with differentiation by fluid type. The values of these parameters, which are used as assessment indicators for identifying promising zones, are derived from a digital model of the studied basin and represented as grids, with each cell assigned a specific parameter value. The threshold values for the TR index, reservoir temperature, porosity and AHRP were determined in accordance with commonly accepted guidelines to differentiate promising and unpromising areas. To identify the most productive zones, the individual maps were created for each criterion, and the regions with the highest degree of overlap among favorable parameters were identified as the most promising areas within the shale succession associated with hydrocarbon accumulations.

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