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https://sciencenorway.no/geology-meteori...ay/1735399

EXCERPTS: Roughly 142 million years ago, a 1.6-km diameter meteorite came hurtling through the atmosphere and crashed into the Barents Sea. The crater it created at the bottom of the ocean was 40 kilometres wide. The rocks on the seafloor were crushed as far down as several kilometres.

Geologists at the University of Oslo (UiO) discovered what was to turn out to be one of the largest impact craters in the world in the 1990s. Since then, researchers have studied the explosion itself, the huge crater that was formed, wildlife and fauna after the explosion - and the giant wave that hit Norway and Greenland because of the impact.

The Mjølnir crater may in fact be one of the best-preserved meteorite craters on Earth. Today it is also a crater that scientists have learned a lot about. “The crater is currently at a depth of 350 metres and is extremely large. It is the 20th largest in the world,” says Henning Dypvik, a professor of geology at UiO. “One of the most special things we have discovered is that the violent explosion actually caused the seabed to burn. A giant fire on the seabed may have lasted for more than 20 minutes, before the seawater returned and put it out,” he said. “This is pretty cool stuff,” the professor says.

He says researchers have discovered soot from the huge Mjølnir fire as far away as Siberia. It’s no wonder, considering that the equivalent of 30 million cubic metres of oil were incinerated in the destroyed bedrock, according to calculations by the UiO researchers.

[...] One thing scientists are more certain about is the giant tsunami that was created by the Mjølnir meteorite. ... Sylfest Glimsdal ... is a senior specialist ... who perhaps knows the most about the Mjølnir tsunami. “The sea was ‘blasted away’ when the meteorite hit,” he said. “The water column that was formed may have been over a kilometre high.”

[...] Glimsdal has also studied what happens when the waves from the impact hit land. “The coast of Finnmark was hit by a tsunami that may have been several hundred metres high. Greenland and parts of northern Russia were also affected. Further south along the coast of Norway, the tsunami was perhaps a hundred metres high,” he said. Glimsdal says that tsunamis that result when giant meteorites strike the sea have a completely different and much greater effect than tsunamis that occur because of earthquakes, for example... (MORE - details)