Okay, on to this week's question.
We love to visit Yellowstone National Park. The hot springs and geysers are out of this world. This geologic wonderland should be on everybody's 'great American pilgrimages' list. We have heard that the Yellowstone area is really a 'supervolcano', capable of gigantic eruptions. Since you are a volcanologist, I hope you can help with my questions. What I want to know is how likely is one of these huge eruptions, who keeps track of volcanic activity there, how much warning would we have, and what would be the consequences? I have seen a scary movie, 'Supervolcano', but don't know how realistic it is. Should we be leery of visiting Yellowstone?
No, don't be worried, and by all means, visit Yellowstone all you wish. Getting run over by a buffalo [or a snowmobile in winter] is more likely to hurt you than volcanic activity. Geologists use the term 'caldera' [Spanish for cooking pot, or cauldron] for volcanoes capable of these gigantic ash eruptions; the media often uses 'supervolcano'. Volcanic activity at Yellowtone is monitored by the Yellowstone Volcano Observatory, [click the link] a branch of the US Geological Survey. Visit their website to get a ton of information about this volcanic wonderland. Especially check out 'Frequently asked questions'. Much of the hype you may hear ('Yellowstone is overdue for a huge eruption'; 'drilling would release pressure'; 'we are all doomed') is dealt with at the YVO website.
|Graphic representing the frequency of hazardous events that occur at Yellowstone. YVO-USGS|
|Areas affected by ash from the last three Yellowstone|
How much warning? Well, geologists believe that premonitory activity would extend over hundreds or even thousands of years. There would be so much warning that some scientists and land managers are concerned that people would grow accustomed to it and no longer take heed. It seems almost impossible to researchers that a gigantic caldera eruption that could harm much of the economy of the US and Canada would occur without lots of prior earthquake activity and smaller eruptions, and so without any warning.
|A 50-foot-high hydrothermal explosion at Biscuit Basin,|
Yellowstone. Photo by Wade Johnson
The typical volcanic eruption at Yellowstone is an isolated lava flow from a vent somewhere in the region. Even these are extremely rare.
There is a great guidebook that any geophile
should take when they visit Yellowstone. It is 'Geology Underfoot in Yellowstone Country' by Marc Hendrix. You can order it from the publisher, Mountain Press Publishers.