Ice age crater discovered beneath Greenland glacier

  • Ice age crater discovered beneath Greenland glacier

Ice age crater discovered beneath Greenland glacier

The Paris-sized crater was discovered with advanced radar technology back in 2015 and recently confirmed, the impact crater is located beneath the Hiawatha Glacier and measures over 980 feet deep and 19.3 miles wide.

The 31km-wide impact site was created between three million and 12,000 years ago and is the first to be found underneath one of Earth's continental ice sheets. The timing is still up for debate, researchers on the discovery team believe the asteroid struck at a moment, roughly 13,000 years ago, as the world was thawing from the last ice age. In the journal Science Advances, researchers make the case that a meteorite perhaps a mile wide slammed into Greenland somewhere between 12,000 and 3 million years ago, reports the Guardian.

The study's abstract says: "The age of this impact crater is presently unknown, but from our geological and geophysical evidence, we conclude that it is unlikely to predate the Pleistocene inception of the Greenland Ice Sheet".

The discovery has been in the making since 2015 after lead study author Kurt Kjær, a geochemist at the University of Copenhagen, found a weird depression under the glacier in maps made by NASA's Operation IceBridge.

This is the first crater of this type ever discovered in Greenland. Let's just hope it is a crater and the buzzing of the drill doesn't hit the nest of something more sinister lurking below the ice.

"We immediately knew this was something special but at the same time it became clear that it would be hard to confirm the origin of the depression", says Kjær.

To confirm their suspicions, in May 2016 the team sent a research plane from Germany's Alfred Wegener Institute to fly over the Hiawatha Glacier and map the crater and the overlying ice with a state-of-the-art ice-penetrating radar provided by the University of Kansas.

"Previous radar measurements of Hiawatha Glacier were part of a long-term NASA effort to map Greenland's changing ice cover", explained Joseph MacGregor, a Nasa glaciologist who helped with the study. The crater formed when a kilometer-wide iron meteorite smashed into northern Greenland, but has since been hidden under almost a kilometer of ice.

The team also put boots on the ground, collecting samples of sediment from channels washing out of the crater, which included bits of shocked quartz that can only be formed during a high-energy impact.

"These rocks and glassy grains are likely produced from impact melting of grains in the meta-sedimentary bedrock", the scientists said.

"A distinctly circular rim, central uplift, disturbed and undisturbed ice layering, and basal debris", MacGregor said in the press release.

"The evidence indicates that the impact probably happened after the Greenland ice sheet formed, but the research team is still working on the precise dating".