Although it was previously assumed that a supervolcano would need an external trigger, such as an earthquake, to start an eruption, scientists have revealed this is no longer the case.

According to The Independent, new research conducted on the dormant supervolcano beneath Yellowstone National Park in the United States has revealed that volcanoes can erupt due to a build up of pressure – and earthquakes aren’t necessarily needed to open the Earth’s crust.

Supervolcanoes are the second largest threat to human life after asteroid strikes. The last known supervolcano eruption was believed to have been in Indonesia around 70,000 years ago. The resulting ash cloud blocked out the sun for 6 – 8 years, and resulted in a period of cooling that lasted for 1,000 years.

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