Activities of the Major Faults and Their Control on Deposition in Haizhong Depression, Beibuwan Basin

The activity rate of Weixinan fault and No.3 fault of Haizhong depression was quantitatively calculated by fault activity rate method. During the evolution of Haizhong depression, the activity rate of Weixinan fault turned strong to week from Changliu period to Weizhou period and the activity of No.3 fault became intensely from Weizhou period. The two faults controlled the development and evolution of Haizhong depression. Moreover, the different active features in different time of the two faults influenced the formation and migration of the deposition center and sedimentation center in this depression. The sedimentation in this depression was controlled by tectonism, and the subsidence also restricted the occurrence and development of the deposition.