GRANITE PEAK PUBLICATIONS: Books accompanying travelers to the Park since 2002

All posts tagged magma

The magma system or reservoir under Yellowstone is 2.5 times larger than previously known

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.’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“.

Share Button

Dynamic Earth: Yellowstone geology doesn’t stay the same

Categories: Science, Thermal features
Comments Off on Dynamic Earth: Yellowstone geology doesn’t stay the same

Yellowstone Treasures‘s geology writing strives to keep up—

If you were to contemplate nature’s many facets and how quickly things change over the seasons and the years, you might think that you can at least count on the rocks and the mountains to stay the same. Wrong! Geoscientists will tell you that even mountains have their own dynamics. But their rate of change is much slower than humans can easily grasp in their relatively short lifetimes. Nature shapes the land we live on over centuries and millennia, but the rate at which geoscientists learn about it using new methods, ideas, and equipment is constantly accelerating.

Wanting to keep track of all this activity as it pertains to Yellowstone Park for the updated fourth edition of my guidebook, I was delighted when my old friend Dr. Jo-Ann Sherwin offered to bring us up to date about Yellowstone’s geology. I’ve known Jo-Ann ever since she was an outstanding student, whose advisor during her Brown University PhD research was my first husband Bill Chapple. She was the first woman to earn a PhD in their geology department and has gone on to a long career in research and teaching. She also lives in Idaho Falls, convenient to the west side of Yellowstone.

Jo-Ann reviewed the entire book and made numerous suggestions. She also rewrote large portions of our geological history essay, “The Stories in Yellowstone’s Rocks.” Our goal is to make our explanations accurate but concise and as clear as possible without any technical writing. Here’s a short sample from our essay that draws upon recent research into the source and age of the water for the park’s thousands of geysers and hot springs (hydrothermal features):

What makes the different hydrothermal features do what they do? Basically, the great volume of groundwater is heated by very hot rocks quite near the surface at Yellowstone.
There is a very large amount of old groundwater, at least 60 but perhaps greater than 10,000 years old, just above the magma below Yellowstone. The source of this water may have been the glaciers that covered the area or rain and snow in the surrounding mountains, 12 to 45 miles (20 to 70 km) distant. Present-day rain and snowmelt seep down and mix with this old water, become warmed to the boiling point, boil into steam, expand greatly, and find a way to escape upward. Most of the features occur where faults are common, making it easy for the heated groundwater and steam to return to the surface.

Share Button