Is it even possible that an impact crater which has even bigger area than Paris can hide underneath ice? The answer is yes! Recently a gigantic impact crater with 31 kilometres wide was found under Greenland’s ice. This crater was recorded in 25 largest craters on earth.
Crater Captain Budd Christman, NOAA Corps [Public domain], via Wikimedia Commons
Thanks to
NASA’s operation ice bridge, an airborne radar which is used to measure the thickness of the ice was applied at the edge of Hiawatha Glacier in northwest Greenland. And then researchers immediately found a round shape implements a massive crater. Although the scientists couldn’t collect the sample from the crater from this time since the crater is still under around 900 meters deep under the ice layer, they collected the
sediment from the water melt from the base of the glacier. In the sediment, they found out some significant signs of the impact:
“shocked” quartz grains with deformed crystal lattices and glassy grains which implements flash-melted rock. This proves that the meteorite which caused this crater was a relatively rare iron meteorite.
To determine the age of this crater, scientists first determine the age of ice sheet covered on the crater which is 11,700 years old. Then researchers found out that the crater has cut through an ancient riverbed formed 2.6 million years ago. That is to say that the crater was probably formed between 11700 years and 2.6 million years old.
From Boliden-Phasen.jpg: Thomas Grauderivative work: Basilicofresco (msg) [Public domain], via Wikimedia Commons
Kurt Kjaer and his team from the University of Copenhagen mentioned that when this kind of big iron meteorite slammed to earth, the impact must cause severe environmental damage around the Northern Hemisphere. Since the crater is likely formed from 11700 and 2.6 million years old, the impact might be the main reason which caused
Younger Dryas which is also known as Ice Age. However, this theory is still a hypothesis and is a lack of convincing evidence.
From Mr. Fred Walton, NOAA via Wikipedia Commons
All in all, a massive crater was found underneath Greenland’s ice and it might be the main reason caused the Ice Age back then. Below is a video shows the whole discovery story if this massive crater.
