Two-staged uplift of the southeast margin of the Tibetan plateau revealed by river longitudinal profiles

The Jinsha River, upstream of the Yangtze flows through southeastern margin plateau, providing an opportunity to study plateau uplift relative Sichuan basin fluvial geomorphology. Eight tributaries River located at transition boundary from were analyzed for feature longitudinal profile and its evolution. spatial distribution slope-break knickpoints in catchment was determined by slope-area analysis integration analysis. Further, magnitude timing base level lowering (i.e., Tibetan Plateau) estimated reconstructing river profile. results show that there are two levels knickpoints, with average elevations 2865 m 1523 m, corresponding relatively 1400 1100 respectively. With reference long-term downcutting rate timings these phases uplifts be ∼21–24 ∼7–13 Ma, These close revealed inversion modeling profiles. Therefore, studied region on Plateau can divided into stages, early stage (∼20 Ma) 1500 2900 late (∼10 4000 which further supports staged outside Plateau.