Images

Temporary webcam deployed on the boardwalk in Biscuit Basin, Yellowstone National Park.  The pan/tilt/zoom camera provides a static view every 15 minutes and records video on site for later download as needed.  Black Diamond Pool, site of a hydrothermal explosion on July 23, 2024, is in the background.  This work was completed under Yellowstone Nation

View looking northwest at a new thermal pool in the Porcelain Basin area of Norris Geyser Basin, Yellowstone National Park, that probably formed in a series of mildly explosive events between late December 2024 and early February 2025.  The rocks and white material (silica mud) surrounding the pool were probably ejected as the feature formed.  The pool is

Yellowstone National Park Geology Program team members Samantha Hilburn (left) and Margery Price (right), both Physical Science Technicians, pose with a snow pit dug near Lewis Canyon for installation of a semi-permanent GPS site, installed in collaboration with USGS scientists. USGS photo by Dan Dzurisin, May 2025.

Map of Yellowstone’s thermal areas. Inset commercial satellite images highlight thermal areas that are mentioned below: Sulphur Hills (©2022, Maxar, USG), Turbid Lake (©2022, Maxar, USG), and Lower Geyser Basin (©2015, Maxar, USG).  This work utilized data made available through the NASA Commercial SmallSat Data Acquisition Program.  We acknowledge th

Photo of the flume in an outflow channel that was used for measuring the volume of water erupted from Old Faithful Geyser. Sandbags were placed to channel the water into the flume and prevent flow under and around it. The study was conducted under research permit YELL-SCI- 08342.

Seismic reflection data showing the top of the magma reservoir beneath Yellowstone Caldera along a cross section that runs from Canyon Village in the northwest (X) to near Lake Butte in the southeast (X`).  The top panel shows seismic P-wave (compressional wave) reflectivity, with evidence for the sharp reservoir top labeled.

Quartz crystals (A) often contain melt embayments (tubular melt-filled pockets burrowed into the side of volcanic crystals) (B), which preserve volatiles (water, carbon dioxide, and sulfur) that have different concentrations in different parts of the embayment (C).

Map showing the Roadside Springs thermal area, located just north of Nymph Lake along the Norris-Mammoth highway.  Hydrothermal ground is shaded purple.  New hydrothermal features formed in 2003 on the north side of Nymph Lake, and also in 2024 a bit further north from the lake.  Figure by Jefferson Hungerford, Yellowstone National Park.

Aerial view looking to the west at the Roadside Springs hydrothermal area and Nymph Lake showing the locations of thermal features that formed in 2003 and 2024.  Yellow line marks the Mammoth-Norris highway.   Figure by Jefferson Hungerford, Yellowstone National Park.

Range of speeds for several animals, athletes, and magmas from various volcanic eruptions. Eruptions shown include the 25,400-year-old Oruanui eruption of Taupo (New Zealand), the 2.08-million-year-old Huckleberry Ridge Tuff of Yellowstone (USA), and the 767,000-year-old Bishop Tuff of Long Valley (USA). Magma ascent rates determined by Myers et al. (2018).

Map of the Northwestern United States showing major volcanic features associated with the mantle plume currently underneath Yellowstone caldera.  Colors indicate general basaltic (blues) versus rhyolitic (reds) compositions, with shades indicating age (darker shades are older).  Rough outlines of calderas that formed due to the Yellowstone hotspot are give

Map of the geologic domains of the Greater Yellowstone Ecosystem (GYE). Boundaries are approximate.

Schematic showing magma storage beneath Yellowstone caldera. Nested calderas resulting from the Huckleberry Ridge Tuff, Mesa Falls Tuff, and Lava Creek Tuff caldera forming eruptions are shown as solid black, green, and orange lines, respectively.

Map of seismicity (red circles) in the Yellowstone region during 2024. 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.

Comparison of steep subduction (like that occurring today beneath the Pacific Northwest of the United States) and flat-slab subduction (which led to the formation of the Rocky Mountains a few tens of millions of years ago). Black arrows indicate the relative direction of movement of the oceanic plate.

Organization chart giving the structure of a response by the Yellowstone Volcano Observatory to a significant episode of unrest or eruption at the Yellowstone volcanic system. The strategy is scalable (elements are activated as they are needed and deactivated when they are no longer needed) and can be adapted to meet the needs of the event response.

Photo and cartoon of 1959 Hebgen Lake earthquake deposit in sediment core from Henrys Lake, Idaho, with references to Cesium-137 activity (or concentration). Changes in Cesium-137 are related to atmospheric nuclear tests and provide a means of dating the deposit; those measurements are plotted on the right with depth (in cm) of the core.

Map of thermal areas from ground-based mapping and remote-sensing methods compiled by Vaughn et al., 2024 (https://www.sciencebase.gov/catalog/item/661d5eb7d34e7eb9eb7e3a41).

Transect of sediment cores from Henrys Lake, Idaho. (a) High‐resolution photoscans and computed tomography (CT) of each core correspond to the location tie line. White line on CT represents gamma ray attenuation bulk density (g/cc). Mapped facies are right of each correspondent core. Shades of gray represent background sedimentation and the event deposit by orange.

Modern vegetation on different geological substrates in Yellowstone.  Left: steppe/grassland on glacial clay found in places like Lamar and Hayden Valleys.  Center: Mixed conifer forest in the Absaroka andesite volcanic field in the eastern part of Yellowstone National Park.  Right: Lodgepole pine forest on Central Plateau rhyolite (hydrothermal grass

Vegetation history based on pollen records from three small lakes on different geological substrates in Yellowstone National Park.   Blue is open vegetation, light green is parkland, dark green is forest.  Top plot is from Slough Creek Pond, in a present grassland area dominated by glacial and lake sediment in the northeast part of Yellowstone Nationa