The Yarlung Tsangpo Valley in Tibet

Excerpt from huffingtonpost.com


Researchers have made a surprising discovery in Tibet, unearthing an ancient canyon buried deep under sediment along the Yarlung Tsangpo River in the southern part of the country.
The canyon is thousands of feet deep in some places and is believed to have been carved by a river three million to seven million years ago. 

“I was extremely surprised,” Dr. Jean-Philippe Avouac, professor of geology at Caltech in Pasadena, Calif. and one of the researchers, said in a written statement. “When I first saw the data, I said, ‘Wow!’ It was amazing to see that the river once cut quite deeply into the Tibetan Plateau because it does not today. That was a big discovery.”

tibet canyon
This Google Earth image looks down the Yarlung Tsangpo valley, where the ancient canyon lies about 800 to 900 meters below the present-day river.

A description of the ancient canyon was published in the journal Science on Nov. 21, 2014.