Volcanic 'flood' linked to extinction
A huge outpouring of molten rock 250 million years ago may have been the decisive factor in the deaths of nearly all lifeforms on the Earth at that time.
The lava that gushed out of the ground was at least twice as extensive as previously thought, a team of international researchers now reports.
Its work suggests the "volcanic flood" was a kilometre and a half deep and covered an area half the size of Australia.
Its timing coincides with the disappearance from the fossil record of up to 90% of all marine species and 70% of land vertebrates.
Researchers suspect the upwelling released vast quantities of gas into the atmosphere, rapidly changing environmental conditions and making it impossible for most lifeforms to continue.
Wider area
Marc Reichow, from the University of Leicester, UK, and colleagues report their findings in the journal Science.
The flood basalts they studied produced the Siberian Traps, volcanic rocks found across a region of Russia called the Siberian Platform.
The Anglo-Russian research team examined rocks taken from deep boreholes in the Western Siberian Basin, nearly 1,000 kilometres west of the Siberian Platform.
From the age and chemistry of the rocks, the researchers determined that they are also part of the Siberian Traps.
The new results suggest that the total extent of the Traps covered around 3.9 million square kilometres. This is equivalent to an area just over half the size of Australia.
Later flood
The Permian-Triassic extinction is the largest, sudden disappearance of life recognised in the fossil record.
Some scientists strongly suspect the impact of an asteroid or comet may also have played a significant role.
American researchers have found chemical traces in rocks from the time which they believe point to an extraterrestrial collision.
Whatever the causes, the mass extinction is believed to have opened the way for the dinosaurs to take charge of the planet.
Their disappearance 65 million years ago has also been linked to a space impactor and another flood basalt event centred on what is now India and Pakistan.
Everyday YOU hear about all the "green" people of today talking about saving and helping the planet. What these "pale yellows" should be worrying about is saving mankind and the species. There is nothing humans can do to destroy this planet. It will simply regroup and come back better than before. On the other hand, civilizations and life have been made extinct many times before. And Yes, we will join that list at some point sooner or later. Bank that!
For a closer look at the planets volcanoes and locations, go toGlobal Volcanism Program Volcanoes of the World Find a Volcano by Region
Long Live Planet Earth,
Bobby Sharpe "Dragon, Book Of Shang": "Dragon, Book Of Shang" "NEW" Reviews & Update Bobby Sharpe's "Animalz": Wolves Protected Again From Idiot Humans
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