The canyon was carved out by a great river more than four million years ago, before the ice arrived.
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Video: Prof Jonathan Bamber describes how the Greenland canyon was discovered
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Greenland's hidden canyon

Posted: Aug 30, 2013 07:48 pm EDT

(Newsdesk) One of the biggest canyons in the world, 800km long and up to 800m deep, has been discovered by accident underneath the Greenland Ice Cap. More than four million years ago, before the ice arrived, it was carved out by a big river, reported BBC. The canyon stretches from the center of Greenland up to the northern coastline and before the ice sheet was formed it would have contained a river gushing into the Arctic Ocean. 

 

Scientists, researching climate change while mapping Greenland’s bedrock by radar, studied the data collected mainly by NASA and researchers from the UK and Germany over decades, were amazed to stumble across the canyon. Prof David Vaughan from British Antarctic Survey (BAS) told BBC News the canyon would have been partly uncovered at the time of the last interglacial 100,000 years ago. "There’s likely some sort of bacteria down there - whether it’s viable is a different matter,” he added.

 

The Ice Cap, up to 3km (2 miles) thick, is now so heavy that it makes the island sag in the middle (central Greenland was previously about 500m above sea level, now it is 200m below sea level). The canyon still runs “downhill”, though, and meltwater from the ice sheet seeps out below sea level at the northern end – at a relative trickle, rather than a torrent. Glaciologists think the canyon plays an important role in transporting sub-glacial meltwater produced at the bed towards the ocean, reported the news source.

 

Previous/Related:

 

AGAP Antarctica findings: Gamburtsev's ghost mountains lived twice

 

New ice-free map of Antarctica

 

Greenland‘s ice sheet shrank only minimally during the Eemian Interglacial

 

Antarctica: Successful drilling through ice at subglacial Lake Whillans

 

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