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Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Science https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ There is another huge impact crater inside Greenland ice

There is another huge impact crater inside Greenland ice



Greenland is included in one of the largest ice layers on the planet, but after its frozen land, the landscape is more captured than we thought.

To bury two kilometers of ice, scientists believe they have found a second huge crater hiding in the northwest corner of the world's largest island

As scientists are increasingly exploring our planet, more and more new craters are being found, especially in icy places such as Greenland or Antarctica

. In fact, before finding the first Hiawatha impact craters in November last year, most experts only believed that any evidence of previous impacts would be destroyed by the fact that these regions are not reluctant to ice erosion.

So it is quite exceptional that in just a few months, what appears to be two of these rarities, both in Greenland, has disappeared.

"We have explored the Earth in various ways: from earth, air and space ̵

1; it is interesting that such discoveries are still possible," says co-author Joe MacGregor, glaciologist with NASA's Goddard Space Flight Center

This discovery was made by combining satellite images and radar data to allow researchers to "see" deeply under the ice. 19659002] It was here that they noticed a circular pattern, only 183 kilometers (114 miles) from the first impact crater. More than 36 kilometers wide (22 miles), the model has been found to have similar properties to adjacent impact craters, namely flat, bowl-shaped depression, surrounded by an enlarged rim and a central tip.

Although not as clearly defined as the Hiawatha Crater, if this second impression is confirmed as a meteorite fingerprint, it will be the 22nd largest impact crater ever found on Earth – three points on one Hiawatha [19659002] a circular structure that could reach this size would have collapsed a volcanic caldera, ”explains MacGregor.

"However, the areas of volcanic activity known in Greenland are several hundred miles away. positive magnetic anomaly, and we don't see it. "

But even if it turns out that Hiawatha has a brother, it is unlikely that the two craters are twins. The authors predict that the second is not only bigger but older

MacGregor and his team concluded that this area had not been disturbed for at least 79,000 years when analyzing nearby ice cores. This may mean two things: that the effect has occurred more than 79,000 years ago; or it happened recently, and the disturbed ice just leaked.

But crater age guessing is a complex business. In this case, the scientists have calculated that the ice would have shrunk the crater to its present form from hundreds of thousands of years to one hundred million years

"The ice layers on this second crater are unequivocally older than those over Hiawatha and the second crater is eroded about twice, ”explains MacGregor.

. Ice over the second crater would be balanced with the crater much faster than Hiawatha.

It is also not uncommon, statistically speaking, that two different meteorites descend so close to each other. Two craters of different age groups are already found in Ukraine and Canada, and computer models have confirmed that these events are unknown in Earth Crater records.

"The existence of a third pair of unrelated craters is modestly surprising, but we don't think this is unlikely," says MacGregor.

"In general, the evidence we have collected shows that this new structure is very likely to be a crater, but at this time it seems to be not double with Hiawatha.

This study was published in Geophysical Research Letters .

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