New Tool Gauges Depth of Old Magma

Giant volcanic supereruptions that spew magma across large areas of a continent haven’t occurred in human history, but they remain a possibility.

"Understanding supereruptive systems is something that we care about," says Ayla Pamukcu. "The Yellowstone hotspot, for example, has been the source of multiple supereruptions in the past and is an active system that could create one again." Bruce McAdam, CC BY-SA 2.0

Giant volcanic supereruptions that spew magma across large areas of a continent haven’t occurred in human history, but they remain a possibility. A new “geobarometer” helps understand how supereruptions could happen.

To understand when and why volcanoes erupt, scientists study the rocks left behind by past eruptions. A method called geobarometry uses the composition of volcanic rocks to estimate the pressure and depth at which molten magma was stored just before it erupted.

A method called geobarometry uses the composition of volcanic rocks to estimate the pressure and depth at which molten magma was stored just before it erupted.