Sunday , January 24 2021

& # 39; Massive meteorite impact crater discovered in Greenland & # 39;



LONDON (Reuters) – Scientists have discovered a 31-km-deep impact crater buried beneath the ice sheet in northern Greenland.

This is the first time a crater of any size has been found on one of Earth's continental glaciers, researchers at the University of Copenhagen in Denmark said.

Researchers have worked in the past three years to verify their discovery, first made in 2015.

The crater measures more than 31 km in diameter, corresponding to an area larger than Paris, and placing it among the 25 largest impact craters on Earth, according to the study published in the journal Science Advances.

The crater formed when an iron meteorite a kilometer wide hit northern Greenland, but has since been hidden under a kilometer of ice.

"The crater is exceptionally well preserved, and this is surprising because glacial ice is an incredibly efficient erosive agent that would have quickly removed traces of impact," said Professor Kurt H Kjaer of the Natural History Museum in Denmark.

"But that means the crater must be quite young from a geological perspective," Kjaer said.

"Until now, it was not possible to date the crater directly, but its condition strongly suggests that it formed after the ice began to cover Greenland, less than 3 million years ago and possibly 12,000 years ago – at the end. last ice age, "he said.

The crater was first discovered in July 2015, when researchers surveyed a new map of the topography below the Greenland ice sheet.

They noted a huge, but undetected, circular depression beneath the Hiawatha glacier, situated on the edge of the ice sheet in northern Greenland.

"We immediately knew this was something special, but at the same time it was clear that it would be difficult to confirm the origin of the depression," Kjaer said.

The 20-ton iron meteorite sits in the courtyard of the Geological Museum in Copenhagen.

"So it was not such a big leap to infer that depression could be a previously unknown meteorite crater, but initially we did not have the evidence," said associate professor Nicolaj K Larsen of the University of Aarhus in Denmark.


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