DINO DOUBLE WHAMMY?
Seismic data from the Atlantic floor off the west coast of Africa collected by Uisdean Nicholson, a geologist at Heriot Watt University in Edinburgh, has revealed the existence of a second major impact crater from around the time of the extinction of the dinosaurs. Nicholson was collecting the data to study plate tectonics, but the results also revealed traces of a massive, ancient crater hidden under about 3,000ft (900m) of water and 1,300ft (400m) of sediment. It showed up as a roughly circular hole approximately 5.3 miles (8.5km) from rim to rim and about 131ft (40m) deep. Deformation of the rock around the hole was consistent with a meteor impact and there was a “central uplift” in the depression, which is a tell-tale sign of an impact. “The crater is very striking, and unlike anything that I had ever seen before,” Nicholson said. While the data strongly points to the structure being an impact crater, to confirm this will require drilling to collect samples to see if the rocks in the crater contain shocked quartz crystals thatChicxulub crater off Central America, widely credited as the site of the impact that caused the extinction of the dinosaurs, raising the possibility that the Nadir Crater could have been caused by another part of the Chicxulub asteroid that broke off in space and hit the Earth within a few hours or days of the main impact. It is impossible to say for certain as the crater can only be dated to within about 800,000 years, and so may be completely unrelated to that impact.
