Massive supervolcanic eruptions can be triggered much more quickly than previously thought, scientists report July 21 in Geology.
The researchers made the discovery while reconstructing the history of a massive eruption 4.5 million years ago in a field of volcanoes called Heise, in what’s now eastern Idaho. The Heise supervolcano spewed enough ash and molten rock to fill Lake Ontario. In most supervolcanoes, magma simmers in underground chambers for hundreds of thousands of years before erupting. But in Heise, the team has determined, several small reservoirs of magma pooled together in less than 10,000 years to spur the eruption.