The magma system or reservoir under Yellowstone is 2.5 times larger than previously known
[Editorial update: On December 18, 2013, USGS research scientist Jake Lowenstern, Scientist-in-Charge of the Yellowstone Volcano Observatory, e-mailed us to provide a clarification of this research:
“They are not imaging the hotspot, which is a global feature that extends into the mantle. They are imaging the shallow magma system that lies in the upper 10 km of the crust and feeds the actual eruptions.”]
Recent articles including “supervolcano” in the headline in the blogosphere and in media such as the New York Post shout “We’re probably doomed” and tell us of “a volcano that could wipe out U.S.” That gets people’s attention! The whirl of media activity is all due to research presented at last week’s American Geophysical Union (AGU) annual meeting in San Francisco.
An interesting session and a poster presented by Drs. Robert Smith and Jamie Farrell have stirred up a lot of emotional response, as has a November earthquake swarm in the area. The more these things are discussed in the media, the less rational readers seem to become. Media loves sensation. Perhaps the scientists whose work inspired the sensationalism will soon issue something to calm people down. Meanwhile, I’ll do what I can with this post.
I attended Smith’s 15-minute session at AGU and read Farrell’s poster last week. I am not a scientist, but I know enough about Yellowstone and current research to say this: The size of the magma reservoir below Yellowstone tells us nothing about when it will explode. Just as a reminder, magma is liquid or molten rock, including any dissolved gases or crystals, found deep within Earth.
More and more researchers are using various methods and instruments (seismometers, strainmeters, geochemical analyses, geodesy, instruments measuring electrical conductivity, and so on) to study what is under Yellowstone and its surroundings. Let’s wish them well and not panic about a catastrophe that is very unlikely to happen within the lifetime of anyone who can read this.
What about those earthquakes? One useful conclusion reached by this recent research is: “A large earthquake at Yellowstone is much more likely than a volcano eruption,” according to Farrell.
ON THE WEB: Here is some reliable and interesting information:
1. University of Utah’s Seismology and Active Tectonics Research Group’s faculty member Bob Smith stated on December 5th that U. of Utah’s seismographs will “continue to monitor Yellowstone earthquakes and will provide additional information if the earthquake swarm activity increases.”
2. U.S. Geological Survey’s Yellowstone Volcano Observatory. Swarms of (usually small) earthquakes have been reported frequently over the years; they are detected by the USGS seismograph array in Yellowstone.
3. Phys.org’s article called “Study: Yellowstone magma much bigger than thought (Update).” A relevant quote serves to sum up my comments here: “For years, observers tracking earthquake swarms under Yellowstone have warned the caldera is overdue to erupt. Farrell dismissed that notion, saying there isn’t enough data to estimate the timing of the next eruption. ‘We do believe there will be another eruption, we just don’t know when,’ he said.”
ON THIS WEBSITE: For more about the quest to understand what’s under Yellowstone, be sure to read the nuggets called “The Yellowstone Supervolcano,” “The Yellowstone Hot Spot: History of the Science“, and “The Yellowstone Hot Spot: Modern Science“.