New satellite data suggests that the world’s largest canyon system may lie under the ice sheet at Princess Elizabeth Land in East Antarctica. The findings were published in the journal Geology.
Using radio-echo sounding data and satellite imagery, scientists believe the canyon system to be comparable in depth to the Grand Canyon, however at 1,100 km (685 miles) in length, it would be many times longer. The canyon is buried under miles of ice at Princess Elizabeth Land, one of the last unexplored regions of Earth’s surface.
Because it’s impossible to explore the land and do field work, scientists assumed that ice surface characteristics in detailed satellite imagery relate to sub-glacial features.
“Antarctic scientists have long recognized 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,” said co-author of the study Dr Neil Ross, of Newcastle University.
“We find evidence that a large, previously undiscovered subglacial drainage network is hidden beneath the ice sheet in Princess Elizabeth Land. We interpret a discrete feature that is 87 x 12.4 miles (140 x 20 km) in plan form, and multiple narrow sinuous features that extend over a distance of 685 miles,” the scientists wrote in the paper.
Lead author of the study Dr Stewart Jamieson, from Durham University in the UK, believes the system was likely carved out by flowing glacial melt, or it’s either so ancient that it was there before the glaciers formed.
Drainage analysis suggests that there may be a sub-glacial lake feeding the canyon system inland – eventually the canyon directs meltwater to the coast between the Vestfold Hills and the West Ice Shelf.
“Linked to the canyons, a large subglacial lake may exist that may be the last remaining large (more then 62 miles in length) subglacial lake to be discovered in Antarctica,” the paper explains.
“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,” concluded Dr Jamieson.