Buried beneath thick slabs of Antarctic ice there lies a craggy landscape, home to mountains, valleys, and โ€“ scientists now know โ€“ a massive, subglacial gorge deeper than the Grand Canyon.

Photo Credit: IceBridge project scientist Michael Studinger captured this photograph of a stunning Antarctic icescape beneath a looming lenticular cloud on November 24, 2013. Beneath the continent's icy expanse lies a rugged terrain scientists are just beginning to chart.

A team of researchers lead by Newcastle University's Neil Ross used radar and satellite imagery collected in collaboration with NASA's IceBridge mission to chart a prehistoric Antarctic mountain range known as the Ellsworth Subglacial Highlands. It was in doing so that they discovered an enormous chasm measuring 1.8 miles deep, 186 miles long and, at some points, as much as 15 miles wide.


By comparison, the Grand Canyon measures longer and, at points, wider than the newly discovered Antarctic trench, coming it at just over 275 miles long and up to 18 miles wide; but where the Antarctic chasm wins out is depth, its profundity extending at points to almost twice that of the Grand Canyon's. (Interestingly, when it comes to sheer vertical extent, neither of these geological rifts can compete with Nepal's Kali Gandaki Gorge; at some points 18,278 feet lower than the bounding peak of Anapurna I, it is arguably the deepest gorge on Earth).


In the latest issue of the Geological Society of America Bulletin, Ross and his colleagues hypothesize that the canyon and the rest of the Ellsworth subglacial highlands formed some 80 million years ago, when the Antarctic continent separated from what was once a unified global landmass, and was later layered over with glaciers that further gouged, and later hid, the lands below them.

"To me, this just goes to demonstrate how little we still know about the surface of our own planet," said Ross in a statement. "The discovery and exploration of hidden, previously unknown landscapes is still possible and incredibly exciting, even now."

Read the full study at the GSA Bulletin.