Researchers used seismic readings to map what is beneath Yellowstone . Partly-molten rock reservoir measures 11,035 cubic miles ( 46,000 cubic km ) It sits 12 to 28 miles ( 19 to 45km ) beneath the national park 's supervolcano . Chamber is 700,000 times bigger than the magma chamber above it - but study said it is not posing any additional threat than it was before .
Researchers used seismic readings to map what is beneath Yellowstone . Partly-molten rock reservoir measures 11,035 cubic miles ( 46,000 cubic km ) It sits 12 to 28 miles ( 19 to 45km ) beneath the national park 's supervolcano . Chamber is four times bigger than the magma chamber above it - but study said it is not posing any additional threat than it was before .