Images

Total electron content (TEC) data—a measure of activity in the ionosphere—at three GPS stations in Yellowstone. Each line color is a measurement using a different satellite passing overhead. Note how the data are steady until the evening of May 10, 2024, when the signals start to fluctuate wildly due to the arrival of the Coronal Mass Ejection.

Photos of Central Plateau Member rhyolite flow structures from the Yellowstone Plateau Volcanic Field. A) An ogive from a road cut along Firehole Lake Drive. Ogives are pressure ridges that form perpendicular to the direction of flow from the compressive stresses that deform the highly viscous lava as it moves.

A mass spectrometer is used to measure the ratio of atoms with different masses—in this case, the different isotopes of argon gas, which can be used to determine the age of a volcanic rock. Left: a side view of a mass spectrometer at the USGS Argon Geochronology Laboratory in Moffett Field, CA. Right: a close-up view of the sample chamber in this mass spectrometer.

Photos of flow breccia in Central Plateau Member rhyolites in Yellowstone National Park. A) Flow breccia observed in a drill core from the Lower Geyser Basin. The angular, light-colored clasts are fragments of the original lava carapace, broken and incorporated into the flow as it advanced. B) Flow breccia exposed in a road cut along Firehole Canyon Drive.

Microscopic view of different groundmass textures in rocks. On the left, this groundmass is a good choice for argon dating, as it consists of abundant interconnected crystals. On the right, the groundmass consists predominantly of glass (black because it does not transmit cross-polarized light) and is a poor choice for argon dating.

Map of the Sawtooth fault, Idaho, based on new lidar topographic maps. Map by Zach Lifton, Idaho Geological Survey, 2024.

Seismic and infrasound data for the April 15, 2024, hydrothermal explosion on Porcelain Terrace at Norris Geyser Basin.  Top plot is seismic data from the YNM station, located at the Norris Geyser Basin Museum.  Middle plot is seismic data from station YNB, in the Ragged Hills of Norris Geyser Basin. Bottom plot is infrasound data from station YNB.&nb

Table showing different types of geochronology techniques, the ages over which those techniques are best applied, and the meaning of the ages determined by the techniques.

Plots showing the number of water samples collected over time (top) and by location (bottom) in the Yellowstone region since the late 1800s. Yellowstone’s archive of water-chemistry research data is a mosaic of scientific progress, built with the work of hundreds of people over more than a century and still growing today.

High-resolution satellite images of Norris Geyser Basin showing the area of Porcelain Basin and Nuphar Lake in April 2024.  In the left image, acquired on April 2, 2024, springs on Porcelain Terrace are full of water, and warm hydrothermal water is flowing into Nuphar Lake, keeping the north part of the lake free of ice.  Boardwalks in the area appear as w

History of travertine deposition in Yellowstone caldera and correlation with past climate conditions. a) The age of travertine samples (based on the U-²³⁰Th geochronometer) from Old Hillside Springs, Hillside Springs, North Hillside Springs, and Morning Glory in Upper Geyser Basin and from Firehole Lake in Lower Geyser Basin.

Schematic illustrating the conditions under which some travertine forms in Yellowstone caldera.

Plot showing the total geothermal radiant power output from Yellowstone’s thermal areas based on Landsat 8 and Landsat 9 thermal infrared images from 2014 to 2024.  Only data from clear, nighttime, wintertime (November through March) dates were used.  The results indicate that there has been no significant change over the last 10 years.

Photo of a bull elk wintering in Yellowstone National Park. Photo by Elizabeth Mordensky, March 5, 2024.

Schematic of the Huckleberry Ridge Tuff magma storage configuration, consisting of discrete batches of magma. Analyzing the compositions of melt inclusions can help paint this type of big picture of the magmatic system. Figure modified from Myers et al. (2016).

Map of the locations of water samples collected in and around Yellowstone National Park and detailed in the USGS Data Release "Historic Water Chemistry Data for Thermal Features, Streams, and Rivers in the Yellowstone National Park Area, 1883-2021." Colors indicate type of water sample.

Illustration of the crystal growth process that leads to melt inclusion entrapment. (a) A crystal (gray area) nucleates and grows. (b) As the magma cools, the crystal corners will grow more efficiently than crystal edges. (c) This growth process will lead to the entrapment of surrounding melt (orange area).

Melt inclusions (<50 micrometers in diameter) in a quartz crystal from the Huckleberry Ridge Tuff, erupted 2.1 million years ago. Photomicrograph taken by Behnaz Hosseini at Montana State University.

Vertical motion at GPS station P720, near the Slough Creek Campground in the northeast part of Yellowstone National Park, clearly shows a large annual cycle.

Histogram showing the number of earthquakes per 3-month period (quarter) in the Yellowstone region during 1973–2023.  Red bars represent all earthquakes located in the area, and blue bars indicate swarm seismicity.

Map of Yellowstone earthquakes that were located during 1973-2023. Red circles are earthquakes located in the Yellowstone region, and blue circles indicate swarm seismicity.  The size of the circle scales with the magnitude of the earthquake.