Supervolcanoes, like Yellowstone’s, may take only centuries to form and erupt

Supervolcanoes — the largest volcanoes on the planet — may take as little as a few hundred years to form and erupt, according to new scientific thinking.

And that could be bad for the US, where a supervolcano is said to be simmering beneath Yellowstone National Park which — if it erupted — risks rendering two thirds of the country uninhabitable, according to the UK Press Association.

Supervolcanoes are fuelled by giant pools of magma, typically 10 to 25 miles across, that form deep underground.

Previously, the BBC wrote, supervolcanoes — which spew out roughly 1,000 times more material than Mount St. Helens did in 1980 — were thought to exist for as much as 200,000 years before releasing their vast underground pools of molten rock.

However, researchers reporting in the May 30 in PLoS ONE have sampled the rock at the supervolcano site of Long Valley in California and found that the magma pool beneath it erupted within as little as hundreds of years of forming.

"Our study suggests that when these exceptionally large magma pools form, they are ephemeral and cannot exist very long without erupting," NBC News quoted Guilherme Gualda, an assistant professor of earth and environmental sciences at Vanderbilt University, as saying in a statement.

If the work holds true for other volcanoes, it means the most powerful eruptions don’t have magma chambers beneath them for very long, according to Science News.

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So if big changes start happening, like new geysers spouting, volcanologists might expect an eruption sooner rather than later.

Yellowstone experienced a supereruption about 2.1 million years ago. 

"The fact that at Yellowstone there’s no giant magma body right now doesn’t mean that in hundreds to thousands of years we couldn’t have one," Gualda said.

"By understanding these time scales better, we know better what to expect."

NBC News, meantime, points out that while there are quite a few supervolcanoes around the world, from Yellowstone Park to what could be a new supervolcano in Bolivia, none of them appears primed for an eruption.

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