Images

Spectrogram of a typical volcano-tectonic (VT) earthquake that occurred near Norris Geyser Basin, in the same region similar depth as the possible long-period (LP) event that was recorded on August 26, 2021.  The top panel shows a 30-second seismogram recorded at seismic station YHH.  The bottom panel shows the spectrogram with energy ranging from 1-15 Hz

Top shows aerial photo of a section of US Highway 191 north of West Yellowstone in Montana. Bottom shows lidar imagery that reveals the road traversing a landslide deposit. High elevations are brown and white, and green is lower elevation. Shading indicates steeper slopes.

Landsat 8 nighttime thermal infrared image of Yellowstone from 28 January 2022.  Inset images are zoomed in on the area outlined by the white square.  Inset image (A) has the raw data values, which range from 9070 to 21284.  Inset image (B) shows the same image converted to spectral radiance, where values range from 3.13 to 7.21 W/m²/micron

Signals from a suspected icequake that occurred on Yellowstone Lake recorded at Yellowstone Seismic Network stations YLA on Lake Butte (top) and YTP at The Promontory (bottom 3 plots). Plot shows about 2 minutes of data from January 24, 2022, starting at about 7:43:34 p.m. MST.  YLA waveform (YLA EHZ) was recorded on a vertical short-period sensor.

Signals recorded at station YDD in Yellowstone National Park from the 2022 Hunga Tonga–Hunga Haʻapai volcanic eruption. The seismometer at YDD recorded both the direct seismic phase (top left) as well as the atmospheric Lamb Wave that coupled to the ground as it propagated (top right).  The infrasound microphone at YDD recorded the atmospheric disturbance

Signals recorded at station YDD in Yellowstone National Park from the 2022 Hunga Tonga–Hunga Haʻapai volcanic eruption. The seismometer at YDD recorded both the direct seismic phase (top left) as well as the atmospheric Lamb Wave that coupled to the ground as it propagated (top right).  The infrasound microphone at YDD recorded the atmospheric disturbance

Comparison of vertical GPS motion measured at station HUSB (top) with earthquake depth (bottom). Red line is a 60-day average of the cleaned GPS time series plotted in gray. Earthquakes are plotted with respect to their magnitudes. The swarm in 2004 represents the vast majority of earthquake in the vicinity of the deforming region.

Map of seismicity (red circles) in the Yellowstone region during 2021. Gray lines are roads, black dashed line shows the caldera boundary, Yellowstone National Park is outlined by black dot-dashed line, and gray dashed lines denote state boundaries.

Time series showing daily vertical GPS positions from the continuous GPS station HUSB between 2001 and 2022.

Scarp of the Uhl Hill fault. Photo (top) is looking west at the east-facing fault scarp, with a geologist at the top of the scarp for scale. Here, the fault cuts through Pinedale-1 glacial deposits just south of a Pinedale-2 end moraine. Plot (bottom) is a scarp profile generated from lidar elevation data.

Boiling River near Mammoth Hot Springs, Yellowstone National Park.  Photo by R. Robinson.

Left photo shows a loose piece of siliceous sinter that was precipitated around a photosynthetic microbial mat in the Lower Geyser Basin.  The microbial mat died when the outflow channel changed positions.

Satellite radar interferogram spanning June 19, 2020, to August 13, 2021, and showing the ground motion in the direction of the satellite.

On the left is Castle Geyser during an eruption with a pool from nearby Tortoise Shell Spring showing photosynthetic pigments at the bottom. The middle image is of a small pool in the Geyser Hill Group in the Upper Geyser Basin with an outflow channel full of yellow, green, orange, red, and brown pigmented phototrophic microbial mats.

Simplified geologic maps showing the difference in mapped rock units from the current, large-scale geologic maps dividing Mount Everts and that join along the boundary between Montana and Wyoming.

Reconstructed fossil horse skeleton found at Hagerman Fossil Beds National Monument, Idaho. National Park Service photo, https://www.nps.gov/articles/000/equus_simplicidens.htm.

Map of the Uhl Hill fault in eastern Grand Teton National Park. Base map is a 1-meter lidar hillshade. Black arrows mark the visible fault scarp, and red lines mark locations where scarp profiles were generated from lidar data or field surveying.

A 200-kilogram (440-pound) fragment of the Canyon Diablo meteorite that was found at Meteor Crater in Arizona.

Michelle Coombs is a volcanologist with the U.S. Geological Survey Volcano Hazards Program. She works out of the Alaska Science Center in Anchorage, Alaska.

Regional map of southeastern Idaho showing the relative location of Yellowstone National Park and the Stanley earthquake aftershocks. Yellowstone National Park (outlined in yellow) is at least 275 km away from the 2020 M_w6.5 Stanley earthquake. Several active faults (in red) are located between the Stanley earthquake and Yellowstone Caldera.

Cumulative number of aftershocks greater than magnitude 2.5 following the March 30, 2020, magnitude-6.5 Stanley earthquake in central Idaho. The black line shows the observed aftershocks, the red line shows the predicted number of aftershocks. Aftershocks are a normal and expected phenomenon following strong tectonic earthquakes.