Present‐Day Strike‐Slip Faulting and Thrusting of the Kepingtage Fold‐and‐Thrust Belt in Southern Tianshan: Constraints From GPS Observations

Abstract

Abstract Across inherited complex fold‐and‐thrust belts (FTBs), shortening may be accommodated at different rates depending on structural style variations; such cases have rarely been documented We present the example of the Kepingtage FTB in southern Tianshan, which is bisected by the NNW‐trending left‐lateral strike‐slip Piqiang Fault (PQF) into eastern and western segments. The 1.45 ± 0.31–2.10 ± 0.42 mm/a shortening rate of the eastern segment is accommodated in a diffuse‐deformation pattern within the five‐row thrust‐anticlinal zone and the 2.36 ± 0.23–3.70 ± 0.59 mm/a shortening rate of the western segment is accommodated within the two‐row thrust‐anticlinal zone at the FTB front. To accommodate the latitudinal variability, the PQF exhibits a 2.30 ± 0.20–4.10 ± 0.40 mm/a segmentation strike‐slip rate. The 2.35 ± 0.33–4.20 ± 0.45 mm/a shortening rate of the Kepingtage FTB and southern Tianshan Fault is one‐third of the total convergence rate between the Tarim Basin and Kazakh Platform at 77°–79°E; hence, the complex Tianshan deformation occurred mainly at the FTB.