Return
Multi-Stage Tectonic Growth of Southeast Tibet Since the Late Cretaceous: Insights From the Jinsha Suture Zone in the Three Rivers Region
X
J
X
P
K
Y
X
DOI:10.1029/2025TC009246.png)
Abstract
En 中文
Reconstructing the deformation and topographic growth history of Southeast Tibet is critical for understanding continental lithospheric dynamics driving Tibetan Plateau development. However, the spatiotemporal pattern of plateau growth and underlying mechanisms remain debated. Here, we investigate the northern Jinsha River fold-and-thrust belt, an inherited structure of the Jinsha suture zone, using low-temperature thermochronology and thermal-history modeling. Our results reveal three episodes of accelerated exhumation: during the Late Cretaceous (ca. 80–68 Ma), Late Eocene (ca. 38–34 Ma), and since the Early Miocene (ca. 19 Ma). The Late-Cretaceous phase is contemporaneous with syn-tectonic sedimentation in the Gonjo Basin, suggesting a coupled tectono-sedimentary system. A regional synthesis of thermochronology data reveals widespread Late-Cretaceous to Early-Cenozoic rapid exhumation in eastern and central Tibet, highlighting the role of Neo-Tethyan subduction and initial India-Asia collision in shaping early topographic relief. The Late-Eocene pulse coincides with magmatism along the reactivated Jinsha suture zone and regional uplift, reflecting a major compressional deformation event. Post-19 Ma exhumation at rates of 150–300 m/Myr is likely linked to Jinsha River incision, although age patterns across the Zigasi-Deqin fault suggest that thrusting also contributed to Early–Middle Miocene exhumation. Integrating our results with published records of deformation, we identify southeastward propagation of compressional deformation since the Late Eocene in northern Southeast Tibet, supporting stepwise plateau growth through crustal shortening. We also infer a possible second phase of southeastward-propagating deformation since the Early Miocene, although this interpretation remains uncertain. Our multi-stage tectonic model provides new insights into the stepwise plateau growth of Southeast Tibet.
Keywords:
Southeast Tibet
Northern Jinsha River fold-and-thrust belt
Jinsha suture zone
low-temperature thermochronology
southeastward propagation
Journal
IF:
3.6
Papers:
3.4K
Citations:
1.5W
