Uplift History of the Southeastern Tibetan Plateau Revealed by Coupled Surface Processes and Orographic Precipitation Model

Abstract The southeastern Tibetan Plateau (SETP) has long been a key region for studying tectonic processes and landscape evolution. However, major controversies remain over the extent of central Tibetan Plateau uplift since the India‐Asia collision, the growth pattern of the SETP, and the roles of precipitation and tectonics on the SETP growth. Here, we use a landscape evolution model that couples surface processes and orographic precipitation to reproduce the landscape evolution of the SETP under changes in tectonic uplift and climate over time and space. We define two end‐member scenarios: one in which the central Tibetan Plateau initially existed as a high‐elevation plateau, and another in which it began at low elevations, with outward plateau growth prescribed in both. Our results show that, irrespective of the initial topographic condition of the central plateau, river‐profile inversions consistently indicate that the eastward extent of uplift in the central plateau was limited to less than ∼400 km east of the source region of the Three Rivers. Further ‐elevation analysis of river profiles suggests that southeastward propagating uplift of the plateau likely initiated by at least the Oligocene. Furthermore, our surface process models, both with and without orographic precipitation, align with the observed topography, implying that orographic precipitation has a minimal impact on the landscape evolution of the SETP. Our study thus provides critical constraints on the tectonic and climatic drivers shaping the SETP.