Mesozoic faults in the NE Tarim (western China) and the implications on collisions in the southern Eurasian margin

Paleozoic and Cenozoic deformation events responding to the continental growth in the southern Eurasian margin since the Paleozoic have been well documented in surface and subsurface geology; in contrast, Mesozoic deformation remains poorly known. Based on interpretation of numerous seismic profiles carried out for oil and gas exploration, a Mesozoic transpressional linked fault system has been identified in the NE Tarim, which is composed of (1) the NW–SE-trending Longkou, Ying-S, Ying-N, and Tienan strike-slip faults to the west, (2) the NE–SW-trending and NW-dipping Ying-E 1 and Ying-E 2 thrust faults as well as their branches to the southeast, and (3) to the north, the Weimak fault which can be divided into NW–SE-trending dextral strike-slip segments and NE–SW-trending, SE-verging segments. The unconformity and growth strata related to activity of these faults occurred from the Jurassic to the Cretaceous. This transpressional linked fault system in the NE Tarim block is a kind of intracontinental deformation, attributed to the collisions of the Qiangtang and Lhasa blocks to the southern Eurasian margin from the Jurassic through the Cretaceous.

► Seismic reflection profiles crossing the NE Tarim block are presented.
► A Mesozoic transpressional linked fault system is identified in the NE Tarim.
► The shortening in the fault system is ∼20 km.
► The fault system is an effect of the collisions of the Qiangtang and Lhasa blocks.