ERUPTING volcanoes led to the great mass extinction at the end of the Permian period 250 million years ago, a new study confirms.
Kliti Grice of the Curtin University of Technology in Perth, Western Australia, and her colleagues believe Siberian volcanoes released greenhouse gases that warmed the planet. This reduced ocean circulation and lowered oxygen levels. As the anoxic zone spread into surface waters, it supported the spread of green sulphur bacteria. Rock samples from China and Australia collected by Grice’s team have confirmed this, showing the bacteria released huge quantities of hydrogen sulphide that would have caused the entire…
