Yellowstone’s Volcanic Plumbing More Extensive Than Believed
by Becky Oskin
Yellowstone’s underground volcanic plumbing is bigger and better connected than scientists thought, researchers reported here today (April 17, 2013) at the Seismological Society of America’s annual meeting.
"We are getting a much better understanding of the volcanic system of Yellowstone,” said Jamie Farrell, a seismology graduate student at the University of Utah. “The magma reservoir is at least 50 percent larger than previously imaged.”
Knowing the volume of molten magma beneath Yellowstone is important for estimating the size of future eruptions.
Geologists believe Yellowstone sits over a hotspot, a plume of superheated rock rising from Earth’s mantle. As North America slowly drifted over the hotspot, the Yellowstone plume punched through the continent’s crust, leaving a bread-crumb-like trail of calderas created by massive volcanic eruptions along Idaho’s Snake River Plain, leading straight to Yellowstone.
The last caldera eruption was 640,000 years ago. Smaller eruptions occurred in between and after the big blasts, most recently about 70,000 years ago…