Type and distribution characterestics of the faults in the B depression of the Zhujiangkou basin,China

The formation and evolution of the B depression in the Zhujiangkou basin were controlled by the tectonic movements,which are Shenghu,Zhuqiong,South Sea movements,and so on.The collision between the Pacific plate and the Asian plate resulted in the shallow NE fault and fold tectonic zone in the basement of the basin.The zone had a simple shape at early stage,but multi-stage extensional movements reformed its characteristics and made the modern structures within the zone very complex.Depending on the seismic interpretation,the drilling analysis and the result of petroleum exploration,the present paper describes the fault type,fault pattern and distribution of faults in detail.The fault type in the study area is normal fault,reverse fault and strike fault.The combination pattern of the faults in the area is feather structure,flower structure,broom structure and detachment structure.The strike of the faults in the B depression includes NWW,nearly EW,NEE,NW,NE,NNW,NNE,NNW and nearly EW.