Magma body beneath Yellowstone supervolcano 20 percent larger than thought

Washington, December 14 (ANI): A new study has shown that the banana-shaped magma chamber of hot and molten rock a few miles beneath the supervolcano in Yellowstone National Park in the US is 20 percent larger than previously believed, which indicates that a future cataclysmic eruption could be even larger than thought.

The studies were led by Robert B. Smith, research professor and professor emeritus of geophysics at the University of Utah and coordinating scientist for the Yellowstone Volcano Observatory.

"Researchers previously believed the magma chamber measured roughly 6 to 15 miles from southeast to northwest, and 20 or 25 miles from southwest to northeast, but new measurements indicate the reservoir extends at least another 13 miles outside the caldera's northeast boundary," Smith said.

He said that the gravity and other data show the magma body "is an elongated structure that looks like a banana with the ends up. It is a lot larger than we thought - I would say about 20 percent (by volume). This would argue there might be a larger magma source available for a future eruption," he added.

Images of the magma reservoir were made based on the strength of Earth's gravity at various points in Yellowstone.

The study also shows a plume of hot and molten rock rising at an angle from the northwest at a depth of at least 410 miles, contradicting claims that there is no deep plume, only shallow hot rock moving like slowly boiling soup.

The rock is still warm from eruptions before the hotspot reached Yellowstone.

"Seismic imaging shows a "slow" zone from the top of the plume, which is 50 miles deep, straight down to about 155 miles, but then as you travel down the plume, it tilts to the northwest as it dives to a depth of 410 miles," said Smith.

That is the base of the global transition zone - from 250 miles to 410 miles deep - that is the boundary between the upper and lower mantle - the layers below Earth's crust.

"At that depth, the plume is about 410 miles beneath the town of Wisdom, Mont., which is 150 miles west-northwest of Yellowstone," said Smith.

According to Smith, "It wouldn't surprise me if the plume extends even deeper, perhaps originating from the core-mantle boundary some 1,800 miles deep." (ANI)