Transpressional uplift of Wensu Uplift in northern Tarim Basin, NW China: evidence from seismic profiles

The Wensu Uplift is an important structural belt in the northern Tarim Basin, NW China, always regarded as a thrust belt. However, this recognition is not only incompatible with the facts that synthetic and antithetic faults are equally developed in thrusting systems on the seismic profiles, but also contradictory with the changeable thrust directions of the main faults. Based on the high-resolution seismic profiles, strike-slip deformation happened in the Wensu Uplift. It is because: (1) Two large flower structures are developed on seismic profiles; (2) The main strike-slip faults named as the Shajingzi and Gumubiezi faults, which are the main faults of two large flower structures mentioned above, thrust violently southward in the eastern section and northward in the western section, respectively; (3) The pre-Mesozoic units in the Wensu Uplift are ancient Sinian-Cambrian strata, which thrust southward and northward over the Mesozoic-Cenozoic strata in the Awati and Wushi sags, respectively. The strike-slip activities happened during the middle Caledonian (the latest Ordovician), the late Caledonian (the latest Silurian), the early Hercynian (the latest Early-Middle Devonian), the late Hercynian (Late Permian), Indosinian-Yanshan (the latest Triassic and Late Cretaceous) and Himalayan period (Paleogene, Neogene and Quaternary). These results indicate that the Paleozoic is not a uniform tectonic-sedimentary environment in the northern Tarim Basin because of the Wensu Uplift barrier.