Scientists have uncovered a ‘lid’ that’s keeping a Yellowstone supervolcano from erupting.
The shocking discovery was made by a team of geologists in an underground reservoir of magma.
The Yellowstone caldera is a volcano in Wyoming, and located around 2.2 to 2.5 miles below the northeastern part, is a magma cap that is stopping an eruption.
The cap is regularly letting out small bursts of gas, which experts say is keeping the event at bay.
Advert
In a press release from Rice University, earth scientist Brandon Schmandt explained: “For decades, we’ve known there’s magma beneath Yellowstone, but the exact depth and structure of its upper boundary has been a big question.
"What we’ve found is that this reservoir hasn’t shut down – it’s been sitting there for a couple million years, but it’s still dynamic."
Schmandt’s team has developed a new method for mapping out the region of the Earth’s crust in the area by sending seismic waves into the ground from a vibrating truck.
Advert
From this, scientists are able to see how the vibrations travel through the rock layers and have been able to create a model of these layers to see what they look like.
Also leading the research team is Chenglong Duan, who has said that these models are the “first super clear images of the top of the magma reservoir beneath Yellowstone caldera.”
The study was published in Nature, where it said: “The stability of hazardous volcanic systems is strongly influenced by the uppermost magma storage depth and volatile exsolution.
“Despite abundant evidence for an upper crustal magma reservoir beneath Yellowstone caldera, its depth and the properties at its top have not been well constrained.”
Advert
“New controlled-source seismic imaging illuminates a sharp reflective cap of the magma reservoir approximately 3.8 km beneath the northeastern caldera.
“Magma ascent to such low pressure is expected to drive volatile exsolution and potentially localized accumulation of bubbles near the top of the reservoir, but this process typically remains hidden in contemporary volcanic systems.”
The study went on to explain: “The results are consistent with partial retention of bubbles exsolved from an upper crustal reservoir with ongoing magma supply from a volatile-enriched mantle source.
Advert
“Bubble accumulation can eventually lead to reservoir instability, but the bubble volume fraction seismically estimated at the top of the reservoir today is lower than typical estimates of pre-eruptive conditions for rhyolites, and measurements of the hydrothermal system document high fluxes of magmatic volatiles escaping to the surface.
“We infer that the magma reservoir is in a stable state of efficient bubble ascent into the hydrothermal system on the basis of estimates that it is a crystal-rich (less than 30% porosity) reservoir for which dynamic modelling favours channelized bubble escape that prevents instability.”