Sergo Ordzhonikidze Russian State University for Geological Prospecting, Moscow, Russia¹ ; Ministry of Science and Education of the Republic of Azerbaijan, Institute of Oil and Gas, Baku, Azerbaijan²

Kerimov V. Yu., Head of Department¹, Leading Researcher², Doctor of Geological Sciences, vagif.kerimov@mail.ru

Sergo Ordzhonikidze Russian State University for Geological Prospecting, Moscow, Russia

Romanov P. A., Lecturer
Mamedov R. A., Associate Professor, Candidate of Geological Sciences

The article examines the results of geological risk assessment during geological exploration for oil and gas in the South Caspian Basin using the Monte Carlo method. The modeling was performed in the risk analysis module of the Petromod software based on the methodology of the Chevron company. As a result of modeling the hydrocarbon systems of the South Caspian Basin, three generation–migration hydrocarbon systems are distinguished: Eocene–Pliocene, Maikop–Pliocene and Miocene–Pliocene. To assess the probability of success and geological risks during geological exploration for oil and gas, the main stage was the analysis of the elements of the hydrocarbon system: oil and gas source strata, reservoir rocks, seals, hydrocarbon traps, as well as the processes of generation, migration and accumulation of hydrocarbons. The results of calculations of the probability of geological success for the South Caspian Basin showed the following values: for the Eocene–Pliocene hydrocarbon system—30.9%, the Maikop–Pliocene hydrocarbon system—65.6%, the Miocene–Pliocene hydrocarbon system—46.1%. The obtained data indicate low geological risks in the studied region. The hydrocarbon saturation of the productive strata section is controlled by mud volcanoes and associated faults and ruptures, and their distribution over the area spatially corresponds to the zones of their development, ensuring the migration connectivity of the oil and gas source strata of the Paleogene-Miocene and the accumulating hydrocarbon intervals of the Pliocene.

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