According to the US Geological Survey, the Yellowstone supervolcano, located in the Western United States, is known to have had three major eruptions between 640,000 and 2.1 million years ago.

It’s been long thought that the volcano was powered by heat from the Earth’s core, like most other volcanoes.

Comparison of volumes of magma erupted from selected volcanoes within the last 2 million years. (USGS)

But, a new study suggests that the volcanic eruptions at Yellowstone were instead caused by hot materials being pushed upward by the Farallon Plate, a huge oceanic tectonic plate, that jammed itself beneath the present-day Western United States about 30 million years ago.

Study author, geoscientist and Virginia Tech associate professor Ying Zhou, says she did not find any proof of heat from coming up the Earth’s core that that could have powered the Yellowstone supervolcano.

She says that she did find an odd underground structure at about 322 to 645 kilometers underneath a line of volcanoes along the Yellowstone hotspot track between Oregon, Idaho, and Wyoming.

The study detailing Zhou’s findings were published in the journal Nature Geoscience