Evidence in Canadian Arctic points to volcanoes as cause of massive extinctionPostMedia News: A mass extinction 250 million years ago was caused by massive volcanic eruptions that burned significant volumes of coal, causing runaway global warming to impact the temperature and acidity of the world's oceans, Canadian researchers found...
'This could literally be the smoking gun that explains the latest Permian extinction,' said Steve Grasby, a researcher at the University of Calgary's department of geoscience. During the Permian extinction 95 per cent of life was wiped out in the sea and 70 per cent on land...
Grasby and his colleagues, Benoit Beauchamp and Hamed Sanei... discovered layers of coal ash in rocks from the extinction boundary in Canada's High Arctic that gives the first direct proof to support the belief that eruptions in what is knows as the Siberian Traps, now found in Northern Russia, produced ash clouds that had a broad impact on global oceans...
At the time of the extinction, the Earth contained one big land mass, a supercontinent known as Pangaea. The environment ranged from desert to lush forest, and the planet was already populated with four-limbed vertebrates. Among them were primitive amphibians, early reptiles and synapsids, the group that would, one day, include mammals.
'The Permian Extinction set the stage for the dinosaurs to take over,' said Grasby... It was a really bad time on Earth. In addition to these volcanoes causing fires through coal, the ash it spewed was highly toxic and was released in the land and water, potentially contributing to the worst extinction event in Earth history,' said Grasby. 'Pockets of life did survive... But it took five million years before it recovered.'
