Researchers have unveiled high-resolution 3D images of the Nadir Crater, a 9 km-wide impact site hidden 300 meters below the Atlantic seafloor. Formed 66 million years ago by an asteroid strike, the crater coincides with the dinosaur-extinction event linked to the Chicxulub impact. The data reveals details of the immediate aftermath, including massive tsunamis and liquefied sediments.
The Nadir Crater, measuring 9 km (about 5.6 miles) across, lies approximately 300 meters (1,000 feet) beneath the Atlantic Ocean floor off the coast of Guinea in West Africa. Discovered in 2022 by Dr. Uisdean Nicholson of Heriot-Watt University while analyzing seismic reflection data, the site appeared as a circular depression over 8.5 km wide, suggesting an ancient asteroid impact.
New three-dimensional seismic data, provided by geophysical company TGS, has confirmed the crater's origin. The asteroid, estimated at 450-500 meters wide, struck at about 20 km per second from 20-40 degrees northeast, forming the crater at the end of the Cretaceous period, around 66 million years ago. This timing aligns with the Chicxulub crater in Mexico, a 200 km-wide feature associated with the mass extinction of dinosaurs.
The images detail the chaotic seconds and minutes post-impact. A deep bowl formed initially, followed by molten rock surging upward and fractured rock spreading thousands of square kilometers. Soft sediments flowed inward, creating a 'brim' around the crater, while earthquake shaking liquefied seabed sediments, triggering faults and large landslides along the plateau margin. Evidence shows a tsunami wave train exceeding 800 meters (2,600 feet) high sweeping across the Atlantic, with resurge scars preserving the event.
Dr. Nicholson described the data as 'exquisite,' noting, 'There are around 20 confirmed marine craters worldwide, and none of them has been captured in anything close to this level of detail.' He compared the 3D imaging to a modern pregnancy ultrasound, revealing internal structures far beyond earlier 2D scans.
Collaborators praised the opportunity. Dr. Sean Gulick of the University of Texas at Austin said the images allow scaling of impact processes for Earth and other worlds. Dr. Veronica Bray of the University of Arizona highlighted the rare combination of subsurface detail and surface preservation, unlike eroded Earth craters or lunar ones lacking internal data.
The findings, published in Communications Earth & Environment, offer a natural laboratory for marine impact studies. Researchers plan to drill the site via the International Ocean Discovery Program to analyze shock pressures and event sequencing.