Rapid Exhumation Processes of the Gaoligong Mountain Range in the Southeastern Margin of the Qinghai–Tibet Plateau Since the Late Cenozoic

Three continent-scale ductile shear zones trending N-S are distributed in the southeast margin of Qinghai–Tibet Plateau. Their tectonic deformation and exhumation histories great significance to understanding orogenic processes within continent growth as well expansion mechanism plateau. The Gaoligong zone (GLGSZ) is westernmost near boundary Indian subduction plate less studied than Ailaoshan–Red River (ASRRSZ) east. In this study, low-temperature thermochronological methods including apatite (U-Th)/He (AHe), zircon (ZHe), fission track (AFT) were used date vertical profile samples from Mountain understand that occurred late Cenozoic. Our results show GLGSZ has experienced two stages rapid events since Cenozoic: middle Miocene (∼14.5 Ma) early Pleistocene (∼2.9 Ma). Based on our data, we divided Cenozoic area into stages: 1) From Miocene, large-scale regional dextral strike-slip movements lateral compressions controlled continuously denuded mountain surface; 2) Pleistocene, river erosion undercutting caused by fluctuations monsoon system, together with continuous activity brittle faults, drove latest exhumations. A comparison data different areas along shows rate its northern transect significantly higher time onset earlier southern transect. These indicate began north continued southwards geomorphological characteristics Mountain, whose elevation part part.