"The supervolcano that lies beneath Yellowstone National Park in the US is far larger than was previously thought, scientists report."
A new study released last week shows that the Yellowstone volcano has a magma chamber more than twice as large as previous estimates. The so-called super-volcano stretches for more than 55 miles and contains between 200 to 600 cubic kilometers of lava.
Underground cavern of lava
A cavern containing the red-hot lava is 20 miles wide and almost two miles deep.
“We’ve been working there for a long time, and we’ve always thought it would be bigger,” said Bob Smith, University of Utah professor and geologist. “But this finding is astounding.”
The volcano study results were presented last week at the American Geophysical Union Fall Meeting in San Francisco.
“We record earthquakes in and around Yellowstone, and we measure the seismic waves as they travel through the ground,” said Doctor Jamie Farrell, of the University of Utah. “The waves travel slower through hot and partially molten material (and) with this, we can measure what’s beneath.”
Last volcano disaster
It’s been a very long time since we had a disastrous volcano in North America. The last major volcano eruption happened 640,000 years ago and covered the continent with ash causing dramatic global cooling. Geologists agree that an eruption now could possibly wipe out human life on the planet.
Scientists say the cavern of molten rock is much further east than was previously thought.
“To our knowledge there has been nothing mapped of that size before,” Dr. Farrell said.
When could the super volcano beneath Yellowstone erupt?
Scientists say they can’t predict when it will erupt but they expect then can give us an early warning by monitoring seismic activity.
"There is no evidence of an imminent volcanic eruption or hydrothermal explosion. That's the bottom line," said seismologist Robert B. Smith, lead author of the study and professor of geophysics at the University of Utah in a press release six years ago. "A lot of calderas [giant volcanic craters] worldwide go up and down over decades without erupting.
Scientists say we are overdue because the Yellowstone super volcano erupts every 700,000 years or so.
Geologists who have studied the Yellowstone volcanto believe the previous Yellowstone supervolcano eruptions occurred about 2 million years ago and 1.3 million years ago.