Tectonically controlled fluvial landforms on the Yaluzangbu River and their implications for the evolution of the river

Abstract

The Yaluzangbu River, the largest river on the Tibetan Plateau, becomes the Brahmaputra when it flows into India. New fieldwork and map analysis show that the fluvial landforms and land-form evolution of the river are controlled by the tectonic structures of the southern plateau. The history of the Yaluzangbu River since the Eocene is established here based on geomorphological and tectonic studies. It includes the formation of the main course along the suture before the Miocene and establishment of downstream course and major tributaries along strike-slip faulting in the Miocene. Also noted are the formation of alternations of wide sections and gorges, gentle and steep hydraulic gradient intervals, and deposition and erosion channel stretches along the river by normal faulting and grabens since the Pliocene.