Grand Canyon '64 million years older than previously thought'

Grand Canyon '64 million years older than previously thought'

Scientists have long argued over the age of the vast canyon, which is more than a mile deep as many as 18 miles wide and 280 miles long.

Most believe it was carved out about five or six million years ago, based on the age of gravel washed downstream by the ancestral Colorado River.

But new dating methods which harness the radioactive decay of uranium showed it is far, far older, according to a study published in the journal Science.

"Our research implies that the Grand Canyon was directly carved to within a few hundred meters of its modern depth by about 70 million years ago," said co-author Rebecca Flowers of the University of Colorado Boulder.

Researchers believe the canyon was probably carved at different times and paces.

http://www.telegraph.co.uk/news/worldnews/northamerica/usa/9713127/Grand-Canyon-64-million-years-older-than-previously-thought.html