Mega-canyon discovered beneath Greenland ice sheet

3D visualisation of the mega-canyon.

Jonathan Bamber, University of Bristol

A previously unknown canyon has been discovered in Greenland, hidden beneath the ice. It is at least 750 kilometers (46.6 miles) long. To put that in perspective, imagine a ten kilometer (6.2 mile) wide gorge, up to 800 meters (0.5 miles) deep, running from the Southern coast of England and into Scotland. This is on the same scale as parts of the Grand Canyon.

Jonathan Bamber, who led the research, was originally mapping Greenland’s bedrock, which was previously thought to be relatively flat and smooth. “Unexpectedly, we found an enormous apparent formation,” he said. “We looked at it in more detail and realized it was a canyon.”

The canyon, which is thought to predate glaciation, has remained hidden beneath two kilometers (1.2 miles) of ice for more than four million years. It has the characteristics of a meandering river channel, an ancient river system that Bamber thinks hasn’t been significantly modified by ice cover.