Researchers find vast chasm hidden beneath the ice of East Antarctica
Deep under the Antarctic ice sheet, there may be a chasm that’s as deep as the Grand Canyon, but many times longer, according to new geologic research led by scientists with Durham University.
The canyon system is made up of a chain of winding and linear features buried under several kilometres of ice in one of the last unexplored regions of the Earth’s land surface: Princess Elizabeth Land (PEL) in East Antarctica.
Very few measurements of the ice thickness have been carried out in this particular area of the Antarctic, and the new discovery needs to be confirmed by direct measurements. But the early finding suggest the canyon may be 1 km deep and more than 1,000 km long.
“Our analysis provides the first evidence that a huge canyon and a possible lake are present beneath the ice in Princess Elizabeth Land. It’s astonishing to think that such large features could have avoided detection for so long,” said lead researcher, Dr Stewart Jamieson, from the Department of Geography at Durham University in the UK.
The researchers believe that the landscape beneath the ice sheet has probably been carved out by water and is either so ancient that it was there before the ice sheet grew or it was created by water flowing and eroding beneath the ice.
Faint traces of the canyons were observed using satellite imagery and small sections of the canyons were then found using radio-echo sounding data, whereby radio waves are sent through the ice to map the shape of the rock beneath it.
The canyons may be connected to a previously undiscovered subglacial lake as the ice surface above the lake shares characteristics with those of large subglacial lakes previously identified. The data suggests the area of the lake could cover up to 1250 square kilometers.
An airborne survey taking targeted radio-echo sounding measurements over the whole buried landscape is now underway with the aim of unambiguously confirming the existence and size of the canyon and lake system, with results due later in 2016.
“This is a region of the Earth that is bigger than the UK and yet we still know little about what lies beneath the ice. In fact, the bed of Antarctica is less well known than the surface of Mars. If we can gain better knowledge of the buried landscape we will be better equipped to understand how the ice sheet responds to changes in climate,” Jamieson said.
In a press release, co-Author Dr Neil Ross from Newcastle University in the UK, said: “Antarctic scientists have long recognised that because the way ice flows, the landscape beneath the ice sheet was subtly reflected in the topography of the ice sheet surface. Despite this, these vast deep canyons and potential large lake had been overlooked entirely.
“Discovering a gigantic new chasm that dwarfs the Grand Canyon is a tantalising prospect,” said co-Author Professor Martin Siegert, from the Grantham Institute at Imperial College London, UK. “Geoscientists on Antarctica are carrying out experiments to confirm what we think we are seeing from the initial data, and we hope to announce our findings at a meeting of the ICECAP2 collaboration, at Imperial, later in 2016.
“Our international collaboration of US, UK, Indian, Australian and Chinese scientists are pushing back the frontiers of discovery on Antarctica like nowhere else on earth,” Siegert said. “But the stability of this understudied continent is threatened by global warming, so all the countries of the world now must rapidly reduce their greenhouse gas emissions and limit the damaging effects of climate change.”