The South Caspian Basin (SCB) is known as one of the oldest oil and gas producing regions in the world. It has more than 100 years of hydrocarbon exploration and development history but still holds large volumes of unexplored resources. To date, a large number of research projects have been carried out to better understand the basin’s development history and thereby to assess and unlock the remaining hydrocarbon potential. Recent geological exploration programs that been carried out in the region have introduced great opportunity to access to the subsurface data, both seismic and drilling, from the areas that never been explored so far. They have played а critical role in mapping subsurface challenges and in more accurate, targeted approach to planning future exploration and development programs in the area. The purpose of this article is to present the results of geochemical studies, geological and geochemical analysis, correlations in the system oil – source rock – mud volcanoes ejecta – well data carried out to describe the history of hydrocarbon fluid formation in the basin, potential mechanisms of hydrocarbon generation and migration as well as geological time of formation and accumulation of hydrocarbons in structural traps. The results of geological and geochemical analysis support the deep origin and genetic identity of the oil and gas samples analyzed. Hydrocarbon formation and migration mechanisms in the area are con-trolled by pressure regime within the source-rock with respect to its surrounding environment of permeable beds. The changes and trends observed in the chemical composition, geochemical properties of the hydrocarbons fluids support the importance of seal capacity, impact of the overlaying cap rocks on type of hydrocarbon fluids and nature of hydrocarbons traps in the area. The timing of petroleum generation from the source rock is consistent with the timing of structural development of some of the hydrocarbon traps in the study area.

 

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