Growth faults in Shenxian depression and their control over the sedimentation

Abstract：As we all know, structure controls sedimentation, while sedimentation controls the reservoir. Lots of sedimentary facies maps, however, were compiled without considering the control of structural factors over the depositional system, which has led to the severe defect that sedimentary facies or/and palaeogeographic maps do not match with contemporaneous structural configuration. Growth faults are the main structural factors, whose activity would control the forming process of sedimentary strata. There were four types of growth faults developed in Shenxian depression in Cenozoic, constituting models of late activity, continuous activity, periodic activity and deep extension. In addiction, based on regional sediments provenance analysis, the authors probed into the control of growth faults over depositional systems, and found that subaqueous fans were developed in the south while deltas were developed in the north. The spread of the fronts of these two depositional systems were further controlled by growth faults, presenting characteristics that lobes spread along faults on the map while wedges overlap in the cross section.