Structural Geometry and Evolution of the No.13 Strike-slip Fault Zone in the Shunbei Area, Tarim Basin

The strike-slip fault zone in the Shunbei area of the Tarim Basin is of typical intracratonic, which is closely related to hydrocarbon accumulation. In this paper, the geometrical deformation characteristics, active periods and active intensities of the No.13 strike-slip fault zone are analyzed based on the interpretations of 3D seismic data, and its formation mechanism is further clarified. The No.13 strike-slip fault zone extends to NNW for more than 100 km, which is characterized by “plane segment, layered deformation and multi-stage activities”. The fault at the deep layer is mainly dominated by the transpression in the north part and translation in the south part. In the shallow layer, the boundary faults have right-step en echelon shape, which form double or multi-fault grabens. The No.13 strike-slip fault zone underwent multiple active stages, and the main part experienced two stages — the Middle Caledonian (the Late Ordovician) and the Late Hercynian (the Middle to Late Permian), while some parts were weakly activated in the Late Caledonian (Silurian). The activity of the fault zone weakened from north to south, and the kinematics indicated that it was a dextral strike-slip fault. The development process of the No.13 strike-slip fault zone is mainly controlled by the main compressive stress from north to south generated by the multi-stage subduction and compression of the Tianshan Ocean in the northern margin of the Tarim Basin, and the fault zone extends from north to south, which is similar to the northern segment of the No.5 strike-slip fault zone. © 2023 Science Press. All rights reserved.