Huge magma Reservoir Discovered Under Yellowstone Could Fill Grand Canyon More Than 11 Times

By Staff Reporter - 24 Apr '15 13:46PM

Scientists have discovered that there is enough magma bubbling in the massive "supervolcano" under Yellowstone National Park to fill the Grand Canyon more than 11 times.

The new discovery is offering researchers more insight into just how huge it really is and helping them to prepare for what may happen if it should ever erupt.

"For the first time, we have imaged the continuous volcanic plumbing system under Yellowstone," says first author Hsin-Hua Huang, also a postdoctoral researcher in geology and geophysics. "That includes the upper crustal magma chamber we have seen previously plus a lower crustal magma reservoir that has never been imaged before and that connects the upper chamber to the Yellowstone hotspot plume below."

The huge bowl-shaped collapsed volcano - known as a caldera -- in the middle of the park last erupted 640,000 years ago. It's one of several large and still active calderas in the U.S.

The newest discovery is a giant chamber hiding beneath another, already known chamber. The threat level of an eruption remains the same, and the chamber just adds to the understanding of the park.

"The new study is the missing link between the shallow magma system that we imaged last year and the mantle plume deep in the Earth," Robert B. Smith, a research and emeritus professor of geology and geophysics at the University of Utah and a co-author on the study, told CBS News. "By putting in this new body we just discovered, it accounts pretty well for the total of the CO2 that comes out of the system."

Since the last major eruption, Smith said the volcano has experienced 50 to 60 smaller eruptions - hundreds of times smaller than the catastrophic ones - most recently about 170,000 years ago. The last one created what is now the West Thumb of Yellowstone Lake. The last lava flow was about 70,000 years ago.

The study was published Thursday in the journal Science.