In Greenland, an international research team has determined the age of a giant crater lying under a layer of ice – 58 million years.
the essentials in brief
- The age of Hiawatha Crater in Greenland has been identified by researchers.
- A good 58 million years ago, a kilometre-long iron meteorite hit the earth.
- Since then, the giant crater has been under a deep layer of ice from the Hiawatha Glacier.
An international research team including ETH Zurich has dated the giant Hiawatha impact crater. The crater is located under a layer of ice in Greenland and is therefore 58 million years old. This is much older than was initially speculated.
The iron meteorite that once hit the earth in north-west Greenland with enormous energy was more than one kilometer in size. The crater that was left behind has been hidden under a nearly one kilometer deep layer of ice from the Hiawatha Glacier.
The crater was discovered in 2018
Researchers first announced the discovery of the crater in 2018. It was not yet possible to date the crater at the time. However, they speculated that the impact event could have taken place around 12,000 years ago.
According to this assumption, the meteorite impact could have heralded the Younger Dryas period. This was a sharp cold snap in Earth’s history at the end of the last glacial period. But that was obviously not the case. Rather, the meteorite crashed into Greenland 58 million years ago.
The research team, led by the Natural History Museums of Sweden and Denmark and the University of Copenhagen, reports this in the journal Science Advances. Consequently, the impact is not related to Pleistocene glaciation.
“A tough nut”
For the study, the researchers age-dated grains of sand and zirconium crystals that they collected downstream of the Hiawatha Glacier. “Dating the crater was a particularly tough nut to crack.” This was said by co-author Michael Storey from the Natural History Museum of Denmark, according to a statement from the University of Copenhagen.
With the determination of the age, the possible effects of the impact on the climate during an important epoch could now be examined. First author Gavin Kenny from the Swedish Natural History Museum added this. Large meteorite impacts can have a lasting and global impact on the climate. However, there is currently no evidence for the Hiawatha impact.
One of the top 25 largest craters
The Greenland impact crater is 31 kilometers in diameter, making it one of the 25 largest on earth. The whole city of Paris would fit into it. However, it falls far short of the Chicxulub crater in what is now the Gulf of Mexico. The meteorite left a crater around 200 kilometers in diameter.
Most likely, this sealed the end of the dinosaurs around 66 million years ago.
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