Produced by: Tarun Mishra
A study published in Nature has revealed that the mass extinction of dinosaurs 66 million years ago was likely influenced by multiple asteroid impacts, not just one.
Researchers mapped an underwater crater off the coast of Guinea, known as the Nadir crater, which spans over 8 kilometres in diameter and was formed by an asteroid approximately 400 meters wide.
The Nadir crater was created by an asteroid that struck Earth at nearly 72,000 kilometres per hour between 65 million and 67 million years ago. Although smaller than the asteroid associated with the mass extinction, it was still powerful enough to have significant geological effects.
The crater's geological features were explored using advanced 3D seismic imaging, revealing details of the impact that were previously unclear. Dr. Uisdean Nicholson, a marine geologist, emphasized the exceptional quality of the images obtained.
The study found that the impact likely triggered intense tremors that liquefied underwater sediments, resulting in faults and landslides extending for thousands of square miles beyond the crater's edge.
The collision is believed to have generated a massive tsunami, estimated to have exceeded 800 meters in height, which would have surged across the Atlantic Ocean.
While the exact timing of the Nadir impact remains uncertain, its discovery suggests that multiple impacts may have occurred around the end of the Cretaceous period, potentially contributing to the extinction event.
Dr. Nicholson noted that the scale of the Nadir impact is reminiscent of the 1908 Tunguska event, which involved a smaller asteroid explosion in the atmosphere over Siberia. The research provides a valuable opportunity to test impact crater hypotheses and develop new models for understanding crater formation in marine settings.