Basement fault activities have influenced on caprock tectonic deformation in Kuqa depression
Yu Haibo1,2, Qi Jiafu1,2, Shi Jun3, Wu Chao3, Zhang Wei3, Fan Sheng1,2, Sun Tong1,2, Yang Xiangyang1,2
1. State Key Laboratory of Petroleum Resource and Prospecting, China University of Petroleum, Beijing 102249;
2. Department of Geology, China University of Petroleum, Beijing 102249;
3. Tarim Oil Company of PetroChina, Korla, Xinjiang 841000
The shrinkage deformation in Kuqa depression has occurred in the integral extrusion of earth's crust or lithosphere scale. Weak rock layers such as plaster-salt layers may lead to local detachment faults. The contraction deformation between the upper salt layers and the lower salt layers is uncoordinated. Under the regional squeeze of some pre-existing basement fault zones, thrust displacement is the main factor to control cap rock of thrust fold deformation. The seismic data, surface outcrop, drilling and logging data and non-seismic data are used to analyze the upper and the lower salt layers of tectonic deformation styles in Kuqa depression. The results show that South Tianshan was uplifted during the squeeze deformation, and thus inducing high angle thrust faults of basement involved between the basin and the mountain transition zone. The resurrection of previous basement faults led to the tectonic deformation in cap rock, the combination styles of basement faults and cap rock faults almost the same on the go, the overlying strong deformation belts of cap rock and the underlying basement fault zones corresponded with each other.