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View Full Version : Did Volcanoes Cause the Great Dying?



Fraser
2005-Sep-07, 06:57 AM
SUMMARY: Something wiped out most of the life on Earth 250 million years ago. Evidence has been building that it was an asteroid or comet strike that made Earth unlivable nearly instantly. But other scientists think that it wasn't instantaneous; instead, they found fossil evidence that the extinction occurred over the course of 10 million years. A group of volcanoes in Siberia spewed out gas continuously that set off a runaway greenhouse effect. Lowered oxygen levels in the atmosphere combined with intense heat would have hit life a deadly double blow.

View full article (http://www.universetoday.com/am/publish/dispute_great_dying.html)
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