Coupled Evolution Between the South Tianshan and Kuqa Basin: Insights From Multisystem Thermochronometers

The intricate interplay of post-collisional magmatism, deformation and related exhumation has reshaped the basin–range system at convergent plate boundaries, as exemplified by the South Tianshan (STS) and the northern part of the Tarim basin (i.e., the Kuqa basin). However, how magmatism, deformation and exhumation interact to control the evolution of the basin–range system remains unclear. This study applies multisystem thermochronometry to elucidate the links between exhumation and post-collisional magmatism, sedimentary burial, thrusting, and deformation at the boundary of the STS–Kuqa basin. Our results reveal that the eastern Kuqa basin experienced rapid exhumation during Permian–early Triassic times, coinciding with volcanic eruptions (ca. 293–288 Ma and ca. 262–254 Ma) and accelerated tectonic subsidence in the western region. The early Permian exhumation was driven by post-collisional continental extension, whereas the late Permian–early Triassic exhumation was associated with regional-scale transpressive strike–slip faults. From the late Triassic to Early Cretaceous, the Kuqa basin experienced continuous burial reheating, corresponding to continuous denudation in the STS during that period. Subsequently, long-term slow denudation in the STS region continued until the early Cenozoic. During the Oligocene–early Miocene, southward thrusting along the North Tarim Fault resulted in the growth and denudation of the STS, coupled with sedimentary burial reheating in the Kuqa basin. Then, deformation continued towards the Tarim basin and intensified since the late Miocene (ca. 5 Ma). The late Cenozoic deformation and exhumation were synchronous with the reactivation of preexisting faults in the STS, and exhibited a progressive westward increase, which can be linked to the clockwise rotation of the Tarim block during the India–Asia collision.