EGU22-11244
https://doi.org/10.5194/egusphere-egu22-11244
EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Propagating uplift controls on high-elevation, low-relief landscape formation in Southeast Tibetan Plateau

Xiaoping Yuan1, Kim Huppert2, Jean Braun2, Xiaoming Shen3, Jing Liu-Zeng4, Laure Guerit5, Sebastian Wolf6, Junfeng Zhang1, and Marc Jolivet5
Xiaoping Yuan et al.
  • 1School of Earth Sciences, China University of Geosciences, Wuhan, China (xpyuan1@hotmail.com)
  • 2Helmholtz Centre Potsdam, German Research Centre for Geosciences, Potsdam, Germany
  • 3National Institute of Natural Hazards, Ministry of Emergency Management of China, Beijing, China
  • 4Institute of Surface Earth System Science, Tianjin University, Tianjin, China
  • 5University of Rennes, CNRS, Géosciences Rennes, UMR 6118, Rennes, France
  • 6Department of Earth Science, University of Bergen, Bergen, Norway

High-elevation, low-relief surfaces are widespread in many mountain belts. However, the origin of these surfaces has long been debated, with previous studies proposing that they either represent a relict low-relief surface, uplifted and eroded by a wave of upstream incision instigated by a Cenozoic increase in rock uplift, or that they formed by tectonic shortening and consequent drainage reorganization. In particular, the Southeast (SE) Tibetan Plateau has extensive low-relief surfaces perched above deep valleys and in the headwaters of three of the world’s largest rivers (Salween, Mekong and Yangtze). Various geologic data, synthesized low-temperature thermochronologic data, and geodynamic models show that many mountain belts grow first to a certain height and then laterally in an outward propagation sequence. By translating this information into a kinematic propagating uplift function in a landscape evolution model, we propose that the high-elevation, low-relief surfaces in the SE Tibetan Plateau are simply a consequence of mountain growth and do not require a special process to form. The propagating uplift forms an elongated river network geometry with broad high-elevation, low-relief headwaters and interfluves that persist for tens of millions of years, consistent with the observed geochronology. We suggest that the low-relief interfluves can be long-lived because of their unusually/unproportionally small drainage area in comparison with the large mainstem rivers. The propagating uplift also produces spatial and temporal exhumation patterns and river profile morphologies that match observations. Our modeling therefore reconciles geomorphic observations with geodynamic models of uplift of the SE Tibetan Plateau, and provides a simple mechanism to explain low-relief surfaces observed in several mountain belts on Earth.

How to cite: Yuan, X., Huppert, K., Braun, J., Shen, X., Liu-Zeng, J., Guerit, L., Wolf, S., Zhang, J., and Jolivet, M.: Propagating uplift controls on high-elevation, low-relief landscape formation in Southeast Tibetan Plateau, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-11244, https://doi.org/10.5194/egusphere-egu22-11244, 2022.