Controlling Effect of Tectonic Activities on the Sedimentation in Passive Rift Basins during the Initial Rift Period: A

In continental rifted basins, the development and distribution of sedimentary facies are controlled by tectonics. Based on the analysis of tectonic features, the tectonic evolution, the establishment of sequence framework and the analysis of sedimentary facies in the AG Formation of Muglad Basin, the AG Formation is considered to be a second-order sequence and can be divided into five third-order sequences. The AG Formation is characterized with three types of sedimentary facies: delta, underwater fan and lacustrine facies. The controlling effect of tectonics on sedimentation is that the direction of the provenance passage is controlled by the fault slope break, which is the area where the sand bodies are accumulated together with the downthrown side of the syn-sedimentation faults. The evolution of the boundary fault controls the change of sedimentary center and the accommodation space, which further controls the distribution of sedimentary facies.