TORONTO – A previously unknown canyon has been found beneath an ice sheet of Greenland.
Scientists discovered the canyon – which resembles a winding river channel and stretches at least 750 km long – using thousands of kilometres of airborne radar data collected by NASA, researchers from the United Kingdom and Germany.
“One might assume that the landscape of the Earth has been fully explored and mapped,” said Jonathan Bamber, professor of physical geography at the University of Bristol in the United Kingdom, and lead author of the study. “Our research shows there’s still a lot left to discover.”
In some places, the canyon is 800 m deep.
Scientists believe that the canyon predates the massive ice sheet that covers it.
The researchers also believe that the canyon plays a role in transporting sub-glacial meltwater from Greenland’s interior to the edge of the ice sheet and into the ocean. They theorize that as long as 4 million years ago, the canyon was a major river system, transporting water to the coast.
“It is quite remarkable that a channel the size of the Grand Canyon is discovered in the 21st century below the Greenland ice sheet,” said Studinger. “It shows how little we still know about the bedrock below large continental ice sheets.”
A large part of the data was collected from 2009 to 2012 using NASA’S Operation IceBridge, which studies polar ice.