Vast sheets of prehistoric lava some 250 million years ago were probably caused by meteorites, according to U.S. scientists.
The huge volume of magma in the lava sheets might have caused global changes in climate that made Earth inhospitable to all but the hardiest species, reported the Guardian Friday.
In a study to be published in November's Earth and Planetary Science Letters, Linda Elkins-Tanton, a geologist at Brown University and Bradford Hager at Massachusetts Institute of Technology say a meteorite with a diameter of less than a mile could dent the Earth's crust enough to weaken it, allowing molten lava as hot as 2,372 F.
"Our computer models show this is absolutely possible," said Elkins-Tanton. "It has deep ramifications for life on Earth -- there's no reason it couldn't happen again."
Copyright 2005 by United Press International
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