A Braided River

The Yarlung Zangbo River winds through Tibet as the world’s highest-altitude major river. Parts of it cut through a canyon deeper than 6,000 meters (three times the depth of the Grand Canyon). And other parts, like this section, are braided, with waterways that shift rapidly from season to season. The swift changes in a braided river’s sandbars come from large amounts of sediment eroded from steep mountains upstream. As that sediment sweeps downstream, some will deposit, which narrows channels and can increase their scouring. The river’s shape quickly becomes a complicated battle between sediment, flow speed, and slope. (Image credit: M. Garrison; animation credit: R. Walter; via NASA Earth Observatory)