A Late Neogene framework and transpressional system within the Yingxiongling Range, western Qaidam Basin, Northeast Tibetan Plateau: Insights from seismic reflection profiles and active tectonics

Abstract

The Yingxiongling Range is a topographically unique and active tectonic belt in the western Qaidam Basin that has recorded the structural evolution and interactions between itself and surrounding ranges throughout the Late Cenozoic. Although a large scale fault-fold system within this region accommodates transpressive deformation, the overall kinematic pattern remains highly debated. Regional seismic reflection profiles, earthquake distributions, focal mechanisms, and displacement vector results are used in this study to rebuild a northern verging thrust and wedge tectonic system in a perpendicular direction. Interpretations of newly acquired three-dimensional seismic data, the timing of growth strata, and the kinematics of active structures strongly support lateral structural deformation propagation and evolution of the southern Yingxiongling Range in the Late Neogene. A novel analysis of active tectonic and seismic profiles enables us to rebuild the framework, kinematics, and evolutionary pattern of the Yingxiongling Range. We also provide a new interpretation of lateral differentia along the Yingxiongling Range based on critical taper theory and suggest that this overall structure is an integrated part of the Qimen Tagh Wedge. Since the Late Neogene, rapid uplift in this area occurred in response to northward propagation of the Qimen Tagh Wedge.