MONO COUNTY, CALIFORNIA — New research has found a huge cache of magma hidden underneath one of the largest supervolcanoes in the world.<br /><br />Forbes reports that California's Long Valley supervolcano erupted some 760,000 years ago, spewing out hot ash, lava, and toxic gas for 6 days that resulted in the formation of a massive caldera.<br /><br />Since 1978, a gradual uplift has been observed in the caldera center, likely from magma flowing into a chamber below the supervolcano.<br /><br />Using seismic tomography, researchers from the USGS California Volcano Observatory were able to show a more detailed view of the subsurface, which they published in the journal Geology.<br /><br />They discovered that the reservoir beneath the supervolcano contained 240 cubic miles of semi-molten magma, 27% of which was in a liquid state.<br /><br />An eruption would require at least 50% of the magma to be liquid, so there's no immediate threat.<br /><br />The bad news is, when Long Valley does eventually erupt, it's likely going to be a massive catastrophe similar to the one from hundreds of thousands of years ago.<br /><br />Since scientists aren't be sure how magma is distributed within the reservoir, normal eruptions are also a possibility, so they're keeping a very close eye on the caldera.
