Volcano Updates

Summary

Yellowstone caldera activity remains at background levels, with 62 located earthquakes in May (maximum = M1.8). Deformation measurements indicate continued caldera subsidence that is transitioning lower rates or slight uplift, which is a signal seen every summer due to seasonal changes in snowmelt and groundwater conditions.

Recent Work and News

Steamboat Geyser erupted on May 30—the third major water eruption of the geyser so far in 2024.

During May 20-22, members of the Yellowstone Volcano Observatory consortium assembled in Mammoth Hot Springs, Yellowstone National Park, where they shared scientific results and discussed monitoring and research priorities.  While in the park, YVO scientists also completed maintenance on GPS and borehole monitoring stations, conducted geological field work, assessed potential sites for new hydrothermal monitoring instrumentation in Norris Geyser Basin, and deployed 15 temporary GPS stations.  These "semi-permanent" non-telemetered GPS sites are installed at the start of every summer and recovered in September/October, and they are intended to densify the existing continuous GPS network.

Seismicity

During May 2024, the University of Utah Seismograph Stations, responsible for the operation and analysis of the Yellowstone Seismic Network, located 62 earthquakes in the Yellowstone National Park region. The largest event of the month was a micro earthquake of magnitude 1.8 located about 14 miles southwest of Old Faithful in Yellowstone National Park on May 11 at 6:08 AM MDT.  

May seismicity in Yellowstone was marked by no new swarms; however, an ongoing minor swarm that began on April 28, located approximately 6 miles north of West Yellowstone, Montana, added an additional 20 earthquakes throughout May, bringing the total number of earthquakes for this sequence to 39. The largest swarm earthquake in May was a magnitude 1.8 event on May 25 at 11:51 AM MDT. 

Earthquake sequences like these are common and account for roughly 50% of the total seismicity in the Yellowstone region.

Yellowstone earthquake activity is currently at background levels.

Ground Deformation

During the month of May, continuous GPS stations in Yellowstone caldera showed subsidence, which has been ongoing since 2015.  Towards the end of the month, data from some stations showed the onset of the annual summertime pause in subsidence or transition to slight uplift, which is caused by seasonal changes related to snowmelt and groundwater conditions.  The caldera has subsided by about 3 cm (1.2 in) since the end of September.  A slight amount of subsidence (about 1 cm, or 0.4 in) has occurred at Norris Geyser Basin over the past three months.

An example of GPS data can be found at http://www.unavco.org/instrumentation/networks/status/pbo/data/NRWY (click on Static Plots / Cleaned)