Cenozoic faults characteristics and regional dynamic background of Panyu 4 sub-sag, Zhu Ⅰ Depression

Key words:  fault development characteristics  genetic mechanism  Cenozoic  Panyu 4 sub-sag  Zhu Ⅰ Depression

Abstract:

Using abundant 3D seismic data, this paper analyzed the static and dynamic characteristics of the fault system of Panyu 4 sub-sag, and then studied its spatio-temporal differences and the mechanisms of the structural transformation. The results show that the development of the fault system in Panyu 4 sub-sag is mainly controlled by the regional evolution of the Circum-Pacific and the Tethyan-Himalayan tectonic domains, and its spatio-temporal differences are also significant. During the rifting stage (E_2w-E_2e), the strike of the strongly active sag-controlling faults changed from NE to NWW and subparallel EW. During the depression period (E_3z-N_1z-N_1h), the activity of those faults decreased and stopped. In the tectonic activation stage (N_1y-Q), the above NWW and subparallel EW pre-existing faults were reactivated and some new subparallel EW faults were developed with significant characteristics of strike slipping. At present the fault system characteristics reflect the superimposed effects of multistage tectonization.