The newly found reservoir has been there all along, but scientists at the University of Utah – Fan Chi-Lin, Hsin-Hua Huang, Robert B. Smith and Jamie Farrell – found it by tracking seismic waves of 5,000 earthquakes. This recently mapped reservoir lies right below the main magma chamber and dwarfs it 4-1⁄2 times.

Image: This how they envision the plumbing looks under the Yellowstone Supervolcano:

Green lines show the boundary of Yellowstone National Park that spans an area larger than Rhode Island or Delaware. The previously known magma chamber shown in orange is about 3 – 9 miles underground and the newly discovered magma reservoir (red) is between 12 and 28 miles below the surface. Under the reservoir is Yellowstone's hotspot plume in yellow, which thrusts up hot rock from Earth's mantle. Previous research showed the plume went down at least 440 miles, but some researchers suspect it originates at Earth’s core, 1,800 miles deep. (Reminds one of that big credibility stretch 2003 sci-fi movie "The Core". Doubtful anything can withstand 11,000ºF that "Earth's saviors" had to endure.)


SCIENCE ALWAYS EVOLVING

This isn't the only new discovery. Last year scientists had to revise the size of the smaller magma chamber. They used to think it was 1,000 cubic miles – about the size of the Grand Canyon – but Farrell and Smith showed the chamber is really 2-1⁄2 times bigger.

They thought something had been "off" with Yellowstone all along because more carbon dioxide gases were being emitted than could be accounted for by just the higher magma chamber.

The four scientists who conducted this latest study are quick to reassure that nothing has changed, there is no rise in the danger level just because they found this massive pot of hot rock. However, "an eruption, the say, could kill as many as 90,000 people almost instantly and release a 10 ft. (3-meter) layer of molten ash 1,000 miles (1,609km) from the park."¹ Such an explosion would trigger a nuclear winter with catastrophic results.

Last year a USGS study concluded that an eruption of this magnitude would cover cities 300 miles away in three feet of ash. Travel and communications would screech to a halt. Roads and highways would be blocked by massive volcanic dust dunes. Food and water supplies would be wiped. Ash weight on top of buildings would cause them to collapse. This wouldn't produce just an ugly day Out West. Prevailing westerly winds would send ash to the East Coast and beyond – around the globe many times. Life as humans knew it – for those who survived – would change forever.

HOLLY NOTE: The USGS recently revised the number of Americans at risk for earthquakes saying FEMA's number of 75 million was way too low. Instead, their data show nearly HALF – more than 143 million lie – in a danger zone. Highest populations exposed to the strongest shaking live in California followed by Washington, Utah, Tennessee, Oregon, South Carolina, Nevada, Arkansas, Missouri and Illinois. Most volcanic eruptions start with earthquakes, sometimes small ones. A mere 5.1 temblor set off Mount St. Helens in 1980 and a Yellowstone eruption is estimated to be 1,000 larger.

¹Source: Zolfagharifard, Ellie, "The Timebomb Under Yellowstone: Experts Warn of 90,000 Immediate Deaths and a 'Nuclear Winter' Across the US If Supervolcano Erupts," UK Daily Mail, August 8, 2015, http://www.dailymail.co.uk/sciencetech/article-3189619/What-happen-Yellowstone-s-supervolcano-erupted-Experts-warn-90-000-immediate-deaths-nuclear-winter-US.html