Synorogenic morphotectonic evolution of the Gangdese batholith, South Tibet: Insights from low temperature thermochronology
The uplift history of the Tibetan Plateau remains one of most intriguing and controversial issues in the Cenozoic history of our planet, and has a significant impact on regional and global climate. Here, we report new low temperature thermochronology apatite and zircon data from the Gangdese batholith in southern Tibet. Thermal history modeling of the data show that the batholith experienced a phase of rapid Early Cenozoic cooling probably associated with exhumation resulting from the initial India Asia's collision, but possibly also due to postarc volcanic activity in the region. The batholith, then transitioned to low erosion rates <0.05 mm/yr) between the Middle Eocene and Early Miocene, followed by a renewed episode of cooling commencing in the Early Miocene. Our results indicate that the Gangdese belt, as the southern margin of Eocene Tibetan Plateau, became plateau like by ~45 Ma. The later cooling episode from Early Miocene onward, can probably be attributed to incision of the ancestral Yarlung River system, cutting through the Gangdese belt by ~22 Ma at the latest.