Images

Pool of boiling water that formed a few days after the June 13, 2026, hydrothermal explosion at Biscuit Basin, Yellowstone National Park, and that is located near the middle vent group of features that formed during the explosion.  The pool is about 6.5 × 5.3 meters (21 × 17 feet) in size and formed via collapse based on the lack of surrounding ejecta.

Aerial view of the Black Diamond Pool area of Biscuit Basin, Yellowstone National Park, showing the locations of northern, middle, and southern vent groups that formed as a result of a small hydrothermal explosion on June 13, 2026.  The "new pool' developed later, between June 14 and 16.

Looking south, toward Black Diamond Pool (steaming blue area in the left middle ground) along a fissure that formed during a small hydrothermal explosion on June 13, 2026, in Biscuit Basin, Yellowstone National Park.  The fissure is about 18.5 meters (61 feet) long and filled with near-boiling water.

Looking downstream along the Firehole River, Yellowstone National Park, from the Midway Geyser bridge on the morning of June 13, 2026.  The milky colors are due to suspended sediment that flowed into the river as a result of a small hydrothermal explosion at Biscuit Basin, which is located a straight-line distance of about 5 kilometers (3.1 miles) upstream.

Screen capture showing the view from the Biscuit Basin research and monitoring camera at 05:09:54 a.m. MDT on June 13, 2026.  Black Diamond Pool is in the foreground, and a steam plume in the upper right marks the occurrence of a small hydrothermal explosion behind (to the north of) the pool.

Hand sample and outcrop photos of Sour Creek dome ash flow (ignimbrite) packages. (A) Package 1 as clasts (see arrow) within lithic breccia in Bog Creek (Wilson et al., 2018). (B) Package 2 with scoria indicated by arrows. (C) Package 3 with increased crystal sizes to all other packages found within dark matrix.

Soccer field overlain on Grand Prismatic Spring in Yellowstone National Park (background image from Google Earth).

Relation between the Lava Creek Tuff and Sour Creek dome at Yellowstone Caldera. (A) Map showing outlines of the two previously mapped outflow sheets (LCT-A and LCT-B) associated with Lava Creek Tuff eruption (modified from Christiansen, 2001; Shamloo and Till, 2019) in and around Yellowstone National Park. Box shows Sour Creek dome study area.

Comparison of caldera-forming eruption sizes (by volume of erupted magma) in the U.S., modified from an AVO/USGS figure. Also included for reference is the 1980 eruption of Mount St. Helens. The three caldera-forming eruptions in Alaska are more than 200 times the size of the 1980 eruption of Mount St.

Infographic giving earthquake, deformation, thermal emission, and geyser statistics for the Yellowstone region for the year 2024.  The graphic accompanies the Yellowstone Volcano Observatory 2024 annual report, freely available online at https://pubs.usgs.gov/publication/cir1566.

Front cover of the Yellowstone Volcano Observatory 2024 annual report, which includes a summary of earthquake, deformation, and geyser activity, as well as research investigations and other information. The report is freely available online at https://pubs.usgs.gov/publication/cir1566.

Google Earth map showing the location of Yellowstone Caldera’s antipode, the Kerguelen Plateau in the southern Indian Ocean, and Heard and McDonald Islands, which host active volcanoes.

Surface imagery and subsurface electrical resistivity tomography results from Rosette Spring in Yellowstone’s Lower Geyser Basin. A) Site Overview: Google Earth imagery of Sentinel Meadows identifying Rosette Spring, Flat Cone, Steep Cone, and Mound Cone. Red lines denote the five parallel NW-SE electrical resistivity tomography (ERT) survey profiles.

Big Ben Volcano on Heard Island. Credit: Australian Antarctic Division (A.J. Graff).

Temperature record from Echinus Geyser outflow channel for February 6, 2026, at 8 p.m. MST to February 7, 2026, at 8 a.m. MST.  The plot shows initial baseline temperatures, then two spikes to 50 °C representing water surges, then an eruption marked by a spike to 70 °C followed by a lull to 10 °C, and finally a return to baseline.

(a) NAIP (National Agriculture Imagery Program) natural-color aerial photograph of Secret Valley Hot Springs, in the backcountry between Norris Geyser Basin and Madison Junction, from September 25, 2015, showing snow-free zone mapping based on snowy wintertime imagery from multiple years. The mapped boundaries of the thermal area are indicated by the orange out

(a) NAIP (National Agriculture Imagery Program) natural-color aerial photograph of Fern Lake, in the east part of Yellowstone National Park, from July 17, 2022, showing mapped locations of liquid water during the winter when the rest of the water body was iced over.  The mapped boundary of the lake is indicated by the orange outline, with shaded areas noting re

Map of horizontal velocities between July and December 2025 at Global Positioning System (GPS) stations P711 and NRWY (arrows and yellow circles; arrow length gives displacement rate) in the area between Norris Geyser Basin and Madison Junction. Dashed black line indicates boundary of Yellowstone Caldera and gray lines are roads.

Map of uplift as seen by interferometric synthetic aperture radar (InSAR) covering the time between October 7, 2024, and October 2, 2025 (the uplift began in July 2025) along the north rim of Yellowstone Caldera to the south of Norris Geyser Basin (NGB). 

Map of seismicity (red circles) in the Yellowstone region during 2025. 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.

Plot of numbers of earthquakes per day in the immediate vicinity of the Norris Uplift Anomaly during 2024-2025.  An increase in the rate of seismicity occurred in September-December 2025, especially in November.  The largest earthquake during that time was M2.7.