Antarctic 'Grand Canyon' Carved by Glaciers

Antartica's underlying topography is revealed in a new map. (Vertical scale has been magnified by a factor of 17.) (Image credit: NASA's Goddard Space Flight Center)

Scientists have discovered a U-shaped gorge that rivals the Grand Canyon in depth, carved by glaciers before West Antarctica was buried in ice. The valley snakes down for more than 15.5 miles (25 kilometers) from the Ellsworth Subglacial Highlands, an ancient mountain range also entombed under the Antarctic Ice Sheet. It is up to 1.9 miles (3 km) deep, besting the Grand Canyon, which is 1.13 miles (1.8 km) at its deepest point. A combination of the weight of the ice sheet and erosion by the glacier that once filled the valley have pushed its elevation down to more than 6,500 feet (2,000 meters) below sea level, Neil Ross, a geophysicist at Newcastle University in the U.K., told LiveScience's OurAmazingPlanet.

The valley is home to Lake Ellsworth, the target of unsuccessful attempts by the British Antarctic Survey to drill into an untouched, buried Antarctic lake. Until now, researchers did not know the extent of the valley, Ross, lead author of a study announcing the find, said. The depth and length of the trench were measured with a combination of satellite data and ice-penetrating radar. The results were published online Sept. 19 in the journal Geological Society of America Bulletin.

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Becky Oskin covers Earth science, climate change and space, as well as general science topics. Becky was a science reporter at Live Science and The Pasadena Star-News; she has freelanced for New Scientist and the American Institute of Physics. She earned a master's degree in geology from Caltech, a bachelor's degree from Washington State University, and a graduate certificate in science writing from the University of California, Santa Cruz.