A plan for monitoring the Yellowstone Volcanic System

Yellowstone Caldera Chronicles is a weekly column written by scientists and collaborators of the Yellowstone Volcano Observatory. This week’s contribution is from Michael Poland, geophysicist with the U.S. Geological Survey and Scientist-in-Charge of the Yellowstone Volcano Observatory.

Map of seismic stations in the Yellowstone region, with numbers of channels indicated by number and sensor type by color.  Inverted triangles indicate stations operated by University of Utah Seismograph Stations (UUSS), and squares indicate stations operated by other agencies.

In 2006, the Yellowstone Volcano Observatory (YVO) published a monitoring plan for the Yellowstone region.  The plan, which covered the 2006–2015 time period, was “to provide Yellowstone National Park (YNP) and its surrounding communities with a modern, comprehensive system for volcano and earthquake monitoring.” 

The plan was ambitious, with numerous goals stretching across disciplines.  For example, YVO argued for the installation of new seismic monitoring sites and upgrading existing sites with digital broadband sensors capable of better detecting seismic activity.  The plan also made the case for new continuous GPS stations, continuous gas-monitoring sites, and temperature-monitoring capabilities.

Many of the 2006–2015 monitoring plan goals were met!  The seismic network was modernized and new seismic and GPS stations were installed, including in remote areas of Yellowstone National Park.  Continuous gas monitoring equipment was tested in multiple locations, and a real-time telemetered temperature-monitoring network was established at Norris Geyser Basin.  All of these data are available on the YVO website.

Some of these monitoring improvements were driven by the National Science Foundation EarthScope Plate Boundary Observatory (PBO)—a nationwide effort to improve deformation and seismic monitoring in the United States (in 2018, PBO was federated into the newly formed Network of the Americas).  In Yellowstone, PBO was responsible for not only the installation of new GPS stations, but also borehole seismic, tilt, and strain instruments.  And in 2009, the American Recovery and Reinvestment Act, also known as the “stimulus,” provided the resources needed to develop the temperature-monitoring network in Norris Geyser Basin.

Map of GPS stations in the Yellowstone region as of 2019. Continuous GPS stations are indicated by green circles, and temporary stations which are deployed in May and recovered in October each year, are red squares.

This year, the Yellowstone Volcano Operatory published a new monitoring plan for seismic, magmatic, and hydrothermal activity in Yellowstone—the “Volcano and Earthquake Monitoring Plan for the Yellowstone Caldera System, 2022–2032.”  The plan is freely available at https://pubs.er.usgs.gov/publication/sir20225032.

The 2022–2032 monitoring plan divides monitoring goals into two categories, “backbone” and “hydrothermal.”

Backbone monitoring refers to region-wide surveillance.  Thanks to work done during the previous 15 years, the backbone monitoring network is already quite strong.  In the coming decade, YVO will focus on continuing to upgrade continuous GPS and seismic monitoring, as well as installing additional stations in places that currently lack continuous observations.  Another important goal is improving hydrological monitoring, including better tracking of the chemistry, flow patterns, and physical properties of groundwater, rivers, and lakes.

Hydrothermal monitoring refers to tracking activity associated with Yellowstone’s thermal and geyser basins.  To date, continuous monitoring has largely avoided the geyser basins because they are “noisy.”  If you want to locate small earthquakes, you would not want to have a seismometer next to a geyser, where eruptions and hot water moving through the subsurface might create noise that would obscure earthquake activity.  In fact, there is currently only one seismometer in Yellowstone that is located in a geyser basin—station YNM, in the Norris Geyser Basin.

Front cover of the Yellowstone Volcano Observatory’s Volcano and Earthquake Monitoring Plan for the Yellowstone Caldera System, 2022–2032.

But hydrothermal regions are important sources of hazard in Yellowstone.  Even small steam-driven outbursts could have serious impacts to anyone that might be nearby—like the 1989 explosion of Porkchop Geyser.  Volcanologists still do not have a good understanding of whether hydrothermal explosions have detectable precursors, but additional monitoring in these regions can provide more insights into this question.

YVO also hopes to expand the scope of gas monitoring in thermal areas.  Yellowstone is not a friendly place for continuous gas monitoring.  Data communication must be done by satellite, which requires significant battery and solar power, and the harsh winters take a toll on the sensitive equipment.  There is currently a continuous gas monitoring station near Mud Volcano, and the coming years will see additional efforts to densify these types of measurements.

The improvements proposed in the “Volcano and Earthquake Monitoring Plan for the Yellowstone Caldera System, 2022–2032” will ensure that the technology used to track seismic, magmatic, and hydrothermal activity in Yellowstone during the next decade remains at the cutting edge of volcanology.  The monitoring strategy will also continue to take advantage of Yellowstone’s status as a premiere natural laboratory to better understand how volcanoes work.

As monitoring in Yellowstone is upgraded and expanded, all data will continue to be available on the YVO monitoring page at https://www.usgs.gov/volcanoes/yellowstone.  Follow along as we learn more about this incredible volcanic Wonderland!

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Jhon Lawrence