Scientists with Washington State University and the University of Idaho have devised a new way to estimate the amount of magma beneath Yellowstone National Park’s supervolcano by measuring the heat lost through the park’s various geologic features.
Jerry Fairley, a professor with the department of geological sciences at the UI and one of the lead researchers on the study, said the new method involved dosing several hot springs with a benign, stable hydrogen isotope called deuterium.
Deuterium, Fairley explained, is a pervasive chemical throughout nature. He said scientists measured the amount of time it took for deuterium levels to return to normal as well as the temperatures of the hot springs to estimate the amount of water running through the system and the amount of heat lost.
Fairley said these measurements are only the tip of geyser.
“We’re interested in how much molten rock is coming up from the mantle of the Earth and feeding the Yellowstone volcano,” Fairley said. “This is something that’s not very easy to know because we’re talking about things that are going on many miles below the land’s surface.”
Fairley said measuring the amount of magma amassing beneath Yellowstone directly informs researchers on the likelihood of an imminent eruption. If magma is coming up slowly, an eruption is probably a long way off, Fairley said.
When magma comes up quickly, it is much more likely that there may be an eruption in the near future. Fairley said this is what is happening with Hawaii’s Kilauea right now.
While their conclusions are still subject to debate, Fairley said the research has shown the magma beneath Yellowstone may be amassing much more quickly than was previously estimated.
“The work that we’ve done, it seems to indicate that there could potentially be up to twice as much heat being discharged as was previously thought,” Fairley said. “If there is twice as much heat coming up as we thought previously, that means there’s twice as much magma coming up.”
Considering the evidence, one might expect geologists to be sounding alarm bells, but Fairley said he doesn’t expect to see a dramatic, full-scale eruption any time soon.
“It’s funny, when people ask me if Yellowstone is going to erupt, as a geologist, I have to say ‘Absolutely,’ ” Fairley said. “Geologists think of things on a little different time scale, so when I say it’s definitely going to erupt, I mean anytime the next 200,000 years.”
Fairley is quick to point out that these values are taken as long-term averages. Magma is not driven to toward the surface in a steady stream but in irregular “blobs,” meaning there is some uncertainty in their estimations. He said the only way scientists will understand the near of Yellowstone is to delve more deeply into research, but, even then, there will be a limit to how much they will be able to learn.
“We can do a better job to prepare, we can do a better job of understanding what the limits of our uncertainties are and we can decrease those limits of uncertainty,” Fairley said, “but volcanoes are big dangerous beasts, and Yellowstone is one of the biggest.”