Methane bubbles trapped in a frozen pool, produced by the decomposing organic matter at the bottom of the pond.

Catastrophic methane release

Catastrophic methane release has been suggested as a possible cause of mass extinction. Methane clathrate is an ice-like substance formed from water and methane in the sea bed, arctic lakes and permafrost. It forms where the temperature is at freezing or a little above and where the pressure of overlying water and sediment creates the right conditions. A temperature rise causes the methane in the clathrate to be released as gas. Global warming results and causes further clathrate heating and methane release. The resultant soaring temperature causes such stress to plant and animal life that mass extinction follows.

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Time period when this happened

Permian period Permian period
The Permian started with an ice age and ended with the most devastating mass extinction the Earth has ever experienced. In fact, at least two mass extinctions occurred during this time.

Contributed to?

Permian mass extinction Permian mass extinction
The Permian mass extinction has been nicknamed The Great Dying, since a staggering 96% of species died out. All life on Earth today is descended from the 4% of species that survived.