Today, the crater lies 700 meters below the sea floor. In fact, in the meantime, the hole has been covered by other types of soil. Geologists discovered the crater in 2002, about 130 kilometers from the Yorkshire coast. At the time, scientists had no unified explanation for the crater’s origin.
They saw an impact of a space rock as one of the possible causes. But many geologists assumed a different theory: they thought the crater was created by the movement of salty rocks under the sea floor.
Geologists at Heriot-Watt University in the Scottish capital of Edinburgh now have evidence that the crater was created by the impact of an asteroid. That happened 43 to 46 million years ago and the asteroid had a diameter of about 160 meters. To illustrate, that’s the size of a cathedral like Notre-Dame in Paris.
The geologists used new seismic images of the sea floor for their research. They created those images by sending sound waves into the ground.
The scientists also took samples from an oil well in the sea floor. In them, the geologists found damaged crystals of rocks. Those crystals are at the same depth as the impact and thus were damaged by the asteroid, the researchers conclude.
“This proves without a doubt the hypothesis of an impact,” said Professor Uisdean Nicholson, who led the research. “This is because the crystals have a structure that could only be formed during an extreme impact.”
After the asteroid’s impact, debris from the seafloor flew about 1.5 kilometers into the air. It also created a tsunami 100 meters high.
According to Nicholson, the crater is well preserved. This is exceptional, as erosion and the shifting of Earth’s plates affect many craters that are often millions of years old. The results of the study may offer more insight into the effects of asteroid impacts.
