Earth's biggest mass extinction 'caused by volcanoes' 250m years ago

  05 October 2017    Read: 437
Earth's biggest mass extinction 'caused by volcanoes' 250m years ago
Earth’s largest ever extinction ever may have been caused by massive volcanic eruptions in Siberia, according to new research, reports citing the Independent.
Around 95 per cent of marine life and 70 per cent of life on land was wiped out in “The Great Dying” about 252 million years ago

The new study published in the Scientific Reports journal, claims the extinction was triggered by the release of more than 200 billion gallons of molten lava over a stretch of land called the Siberian Traps.

Scientists found spikes in the amount of nickel – an element formed by volcanic magma – in rocks dating from the period also known as the Great Permian Extinction in countries around the globe, including China, Israel and Hungary.

But it was the huge volume of sulphur dioxide and carbon dioxide released into the atmosphere that caused the planet to become close to uninhabitable. First Earth cooled by a few degrees before warming it by about 14 degrees Fahrenheit and triggering acid rain.

Michael Rampino, New York University geologist and the paper’s senior author, said: “The Siberian volcanic eruptions and related massive intrusions of nickel-rich magmas into the Earth’s crust apparently emitted nickel-rich volatiles into the atmosphere, where they were distributed globally.

“At the same time, explosive interactions of the magma with older coal deposits could have released large amounts of carbon dioxide and methane, two greenhouse gases, which would explain the intense global warming recorded in the oceans and on land at the time of the mass extinctions.

“The warm oceans also became sluggish and depleted in dissolved oxygen, contributing to the extinction of many forms of life in the sea.”

Sedelia Rodriguez, co-author of the paper and lecturer in the department of Environmental Science at Barnard College, added: “This new finding, which contributes further evidence that the Siberian Trap eruptions were the catalyst for the most extensive extinction event Earth has ever endured, has exciting implications.”

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