Fault characteristics and division of tectonic units of the thrust belt in the front of the West Kunlun Mountains
西昆仑山前冲断带断裂特征及构造单元划分

The arc-shaped thrust belt in the front of West Kunlun Mountains formed in Cenozoic with the northward thrust and lateral rotation of Pamir syntax. We here present our new field investigation and seismic profile interpretation data to study the fault system, which provides the basis to understand the complex arc-shaped foreland thrust belt. The results indicate that the thrust belt mainly consists of thrust faults with consistent striking to the arc shape of the thrust belt, but in the middle portion occur some thrust fault holding dextral strike-slip component. Also occur NE-SW and E-W trending strike-slip faults, which differs in their active timing and mechanisms. These NE-SW and E-W trending faults control the deformation of the thrust belt and accommodate and reconstruct previous existing structures. Based on the study of fault system, determination of deformation time and structural characteristics of different portions, the arc-shaped thrust belt has been divided into 9 tectonic units. After formed in Middle-Late Miocene, the thrust belt experienced four evolution stages: Early Pliocene, Middle-Late Pliocene, early-middle Early Pleistocene and late Early Pleistocene.