After years of discussion, researchers now confirm that the Silverpit Crater in the North Sea was formed by an asteroid impact over 40 million years ago. This crater, first identified in 2002 and located about 80 miles off the Yorkshire coast, stretches 1.8 miles wide and lies 766 yards beneath the seafloor.
Initially, its circular shape and central peak hinted at a cosmic impact. However, some scientists speculated that it might be a result of shifting salt deposits or ancient volcanic activity.
Led by Uisdean Nicholson from Heriot-Watt University, a recent study has settled this debate. Using modern 3D seismic imaging alongside drill samples from a nearby oil well, the team gathered compelling evidence. These findings confirm the crater’s origin ties directly to an asteroid strike.
Nicholson remarked that Silverpit is “a rare and exceptionally preserved hypervelocity impact crater.” This discovery helps us understand how such events have influenced our planet and what might occur in future asteroid collisions.
The new seismic data revealed clear impact features: a raised central area, a surrounding moat, shattered rocks, and smaller craters caused by debris. It appears the asteroid struck from the west at a shallow angle, as suggested by the rock patterns around the crater.
Microscopic analysis of drill samples revealed quartz and feldspar grains with unique markings. Nicholson noted the discovery of these grains was akin to finding “a needle in a haystack.” These markings only form under extreme pressures, solidifying the asteroid impact theory.
Models suggest the asteroid was about 175 yards across, moving over 9 miles per second. Upon impact, it created a plume of rock and seawater nearly a mile high, leading to a tsunami over 100 meters tall. The impact occurred during the middle Eocene, approximately 43–46 million years ago.
In 2009, many geologists sided with the theory of a non-impact origin for the crater, considering it resolved. Nicholson initially supported this view but later followed up on a tip suggesting a reevaluation of Silverpit.
Old seismic records and new high-resolution data finally aligned, corroborating the asteroid impact narrative. Gareth Collins, a planetary scientist at Imperial College London, expressed the relief of confirming this hypothesis. He stated the impact theory consistently aligned with the observations.
Moreover, the preservation of the crater, including a flat-topped uplift, is notable for scientific study. Impact craters are rare on Earth, with fewer than 250 confirmed sites globally, and only 33 beneath oceans. Silverpit now joins the ranks of the Chicxulub crater, linked to the dinosaurs’ extinction, and the newly identified Nadir Crater in Africa.
This research, published on September 20 in Nature Communications, opens new avenues for understanding past catastrophic events and preparing for potential future impacts.
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