The newest fault system and channels of long-distance lateral migration of hydrocarbons within the North-West Caspian Sea

Features of regional geodynamic conditions for the development of the North- West Caspian Sea territory at the latest stage of geological history and their important role in the hydrocarbon deposits formation (young age of structures and deposits, connection with the fault system) are shown in the article. Modern ideas about the formation of oil and gas deposits in the North-West Caspian Sea due to long-distance lateral migration of hydrocarbons (there are no conditions for the formation of oil and gas at their location) are given. These studies are aimed at establishing the main channels of the newest long-distance lateral hydrocarbons migration through a complex analysis of geochemical and neotectonic (morphometric) data. Within the North-West Caspian Sea a fault system was determined, which experiences neotectonic activity and detailed analyses are given. Five different groups of oils have been established, according to the different isotope composition of carbon oils, indicating five sources of hydrocarbon generation. It was established that in the history of oils there were no cardinal changes in the conditions of their existence, on the basis of homogeneous isotope composition of oil fractions. For the first time, the main channels of long-distance newest lateral hydrocarbons migration have been mapped within the North-West Caspian Sea, according to the established «kinship» of oils and structure of newest fault system. © 2025 Elsevier B.V., All rights reserved.