Integrated seismic interpretation and geological study on the west branch of the East African Rift System demonstrate that the growing rift basin is controlled by the properties of basin’s basement. So that, the high-angle graben is developed in the rift system. Divergent and convergent accommodation structures are developed along the trend of the system. Horst and graben are the main accommodation structures in the dipping direction of the main faults. Tectonics and structures controlled the main petroleum conditions: High-angle graben rift can form extensive and thick lacustrine sediments containing high-quality hydrocarbon source rock; inter-rift accommodation structure is the first-class accommodation belt which controls the distribution of the braided river delta; intra-rift broken boundary faulting zone belongs to secondary strike accommodation structure which controls the development of small- and medium-sized fan delta. Faulted nose and block traps controlled by the accommodation structure along the fault dipping direction are the primary reservoirs in this type of basin.
Chen Xi Wen Zhixin Zhang Guangya Wang Zhaoming Song Chengpeng. The tectonic style of the west branch and its control action to hydrocarbon accumulation in the East African Rift System[J]. Chinese Journal of Geology, 2017, 52(2): 407-415.