ABERDEEN, Scotland, Aug. 27 (UPI) -- A U.K. researcher says the theory of a meteor impact killing off dinosaurs needs to be tweaked at bit, suggesting there was not one but many cosmic collisions.
Previously, scientists pointed to a huge impact crater in the Gulf of Mexico as evidence of the event that spelled doom for the dinosaurs, but now evidence for a second impact in the Ukraine has been uncovered, the BBC said.
An article in the journal Geology by a team lead by Professor David Jolley of Aberdeen University says the discovery of a second crater suggests the extinction was caused by a "double whammy" instead of one isolated strike.
Proposed in 1980, the theory that a meteorite impact killed off the dinosaurs was controversial until the discovery of the huge Chicxulub Crater in the Gulf of Mexico. Now examination of the Boltysh Crater in the Ukraine shows it was the first of two major impacts, only several thousand years apart, and evidence from later layers of sediments that filled the crater matches the timing of the Gulf of Mexico impact.
"We interpret this second layer as the aftermath of the Chicxulub impact," Professor Simon Kelley of the Open University says.
Rather than being wiped out by a single hit, researchers think dinosaurs may have fallen victim to a meteorite shower raining down over thousands of years.
"It is quite possible that in the future we will find evidence for more impact events," Kelley says.
