Petroleum accumulation conditions and exploration direction of Rio Muni Basin, West Africa

Based on the background of regional structural evolution, the tectono-sedimentary evolution of Rio Muni Basin, West Africa can be divided into three phases: intracontinental rift, intercontinental rift and passive continental margin. It has been proved by exploration and research that there are multilayer source rocks, reservoirs and caps in the basin. With the Aptian Salt developed in the intracontinental rift phase as the interface, there are pre-salt and post-salt petroleum systems. It is showed that salt structures and favorable reservoirs control the effective hydrocarbon accumulation of the post-salt system, while high-quality source rocks and caps are the key reservoir forming factors of the pre-salt system. It is recognized by comprehensive analysis that the petroleum exploration focus should be the Cretaceous on the salt and the complex hydrocarbon reservoirs with structure stratigraphy with the development of salt structure and turbidite sand body. It is suggested that the near-source favorable structures are priority exploration targets to the pre-salt strata in the area located in the hydrocarbon generation center of rift sag.