After two decades of debate, researchers say they finally have definitive proof that the Silverpit Crater, a buried structure in the North Sea, was created by an asteroid strike more than 40 million years ago.
The crater, discovered in 2002 about 80 miles (129 kilometers) off the Yorkshire coast, is 1.8 miles (3 km) wide and lies some 766 yards (700 meters) below the seafloor. Its circular shape and central peak look like hallmarks of a cosmic impact — but in the absence of definitive evidence, alternative explanations emerged. For instance, there were theories that shifting underground salt deposits or ancient volcanic activity could be responsible for the structure.
Now, a team led by Uisdean Nicholson of Heriot-Watt University in Scotland has solved the mystery at last. Using modern 3D seismic imaging and drill cuttings from a 1980s oil well, the researchers pieced together the clearest picture yet of the crater, confirming its asteroid impact origin.
“Silverpit is a rare and exceptionally preserved hypervelocity impact crater,” Nicholson said in a statement. “We can use these findings to understand how asteroid impacts shaped our planet throughout history, as well as predict what could happen should we have an asteroid collision in future.”
The new seismic data provided an “unprecedented look” at the structure, revealing unmistakable impact features, including a central uplift, an encircling moat, shattered rock zones and even smaller “secondary craters” carved by falling debris, the study reports. The pattern of faults around the crater — with rocks pulled apart on the west side and compressed on the east — suggests the asteroid slammed in from the west at a shallow angle, researchers say.
Microscopic analyses of drill samples were the smoking gun: rare grains of quartz and feldspar etched with microscopic scars that form only under the extreme pressures of a hypervelocity impact, not by any Earth-bound process.
“We were exceptionally lucky to find these — a real ‘needle-in-a-haystack’ effort,” Nicholson said in the statement. “These prove the impact crater hypothesis beyond doubt, because they have a fabric that can only be created by extreme shock pressures.”
Computer models that built on the evidence suggest the impactor was an asteroid about 175 yards (160 meters) across — roughly the length of one and a half football fields — traveling at more than 9 miles per second (15 kilometers per second). The strike blasted a 1-mile-high (1.5-kilometer-high) plume of rock and seawater into the sky before collapsing into a tsunami more than 109 yards (100 meters) tall.
The seismic record also shows the event took place during the middle Eocene, between 43 million and 46 million years ago.
The debate over the crater’s origins came to a head in 2009 at a Geological Society meeting in London, where the vast majority of the geologist attendees voted for the non-impact origin.
“For many, that was the final word,” Nicholson reflected in a separate post on Springer Nature’s “Behind the Paper,” where researchers recount the backstory of their research. “I must admit that I had bought into the prevailing wisdom that the structure had a much more mundane origin, and that the evidence was stacked against it.”
Two decades after Silverpit was discovered, Nicholson and colleagues revisited the controversy almost by chance. In 2022, fresh off the discovery of the Nadir Crater off West Africa, the team received a tip from a colleague at the North Sea Transition Authority urging them to take another look at Silverpit, the post says.
Examining old seismic records and new data from high-resolution surveys, drill cuttings and impact simulations, the team found converging evidence that Silverpit was carved by a violent asteroid strike, not mundane geology.
“I always thought that the impact hypothesis was the simplest explanation and most consistent with the observations,” study co-author Gareth Collins, who is a professor of planetary science at the Imperial College London, said in the statement. “It is very rewarding to have finally found the silver bullet.”
The crater’s unusual preservation, including a flat-topped, pitted central uplift that may record intense chemical reactions immediately after the strike, makes it especially valuable to science, researchers say.
Impact craters are vanishingly rare on Earth, where erosion and tectonic activity erase most traces over time. Fewer than 250 confirmed sites exist worldwide, and only about 33 have been identified beneath the oceans.
Its confirmation now places Silverpit alongside Mexico’s Chicxulub crater — linked to the extinction of the dinosaurs — and the recently identified Nadir Crater off West Africa.
“This exceptionally preserved structure can continue to provide important information on what happened during this specific event,” Nicholson wrote in the Behind the Paper post, “but also what might happen if a similar event were to occur in the future.”
This research is described in a paper published Sept. 20 in the journal Nature Communications.
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