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Re: Our Palisades forming caused a global mass extinction which paved way for dinosaurs
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Scientists examining evidence across the world from New Jersey to North Africa say they have linked the abrupt disappearance of half of earth's species 200 million years ago to a precisely dated set of gigantic volcanic eruptions. The eruptions may have caused climate changes so sudden that many creatures were unable to adapt?possibly on a pace similar to that of human-influenced climate warming today. The extinction opened the way for dinosaurs to evolve and dominate the planet for the next 135 million years, before they, too, were wiped out in a later planetary cataclysm
The scientists analyzed samples from what are now Nova Scotia, Morocco and the New York City suburbs. (Olsen hammered one from a road cut in the Hudson River Palisades, about 1,900 feet from the New Jersey side of the George Washington Bridge.) Previous studies have suggested a link between the CAMP eruptions and the extinction, but other researchers' dating of the basalts had a margin of error of 1 to 3 million years. The new margin of error is only a few thousand years?in geology, an eye blink. Blackburn and his colleagues showed that the eruption in Morocco was the earliest, with ones in Nova Scotia and New Jersey coming about 3,000 and 13,000 years later, respectively. Sediments below that time contain pollen, spores and other fossils characteristic of the Triassic era; in those above, the fossils disappear. Among the creatures that vanished were eel-like fish called conodonts, early crocodilians, tree lizards and many broad-leaved plants. Read more at: http://phys.org/news/2013-03-ties-meg ... -mass-extinction.html#jCp
Posted on: 2013/3/22 20:14
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Our Palisades forming caused a global mass extinction which paved way for dinosaurs
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Posted on: 2013/3/21 20:58
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