Images

Simplified map of Arizona and western edge of New Mexico, showing the location of the Uinkaret, San Francisco, and Springerville volcanic fields as shaded gray areas as well as the locations of Flagstaff, Springerville, and Phoenix for reference. The Colorado Plateau is shown in a light orange color.

View from a research camera installed at Biscuit Basin near the site of seismic, infrasound, and GPS monitoring. The camera has a view of Black Diamond Pool, where a hydrothermal explosion occurred on July 23, 2024, as well as of the area north of the pool where another small explosion occurred on June 13, 2026.  Camera images are updated every 15 minutes

Camera installed at the Biscuit Basin monitoring site. The camera is near the top of a small tower that holds a weather sensor and solar panel that powers nearby seismic and acoustic sensors.  The solar panel that powers the camera is located on the ground at the base of the tower.  USGS photo by Mike Poland, July 22, 2026.

Black Sand Pool, in Yellowstone National Park's Upper Geyser Basin.  The hot spring is known for it's thumping behavior, which occurs every few minutes due to collapse of bubbles within the spring.  The thumping is strong enough to be heard and felt by anyone nearby.  USGS photo by Mike Poland, July 21, 2026.

Google Earth image of the newly proposed Idaho Volcanic Field, with recent eruptions indicated, and Craters of the Moon lava field. Major city centers surrounding the volcanic field are included to provide spatial context.

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.

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.

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.

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.

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.

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.

Simulated (not from actual data) soccer heat maps for different positions: (A) goalkeeper, (B) central defender, (C) right winger, and (D) striker.

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.

The Alaska-Aleutian Subduction Zone hosts the highest concentration of active volcanoes in the U.S. (orange triangles). Of these, several are caldera systems, with three notable examples highlighted (red triangles). Photos of Okmok, Fisher, and Aniakchak Calderas are shown in the lower panels. Digital shaded-relief map of Alaska from the USGS.

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.

Episode 43 of the ongoing Kīlauea summit eruption occurred on March 10. Lava fountains from the north and south vents on the western side of Halema‘uma‘u crater floor produced a large eruption plume of volcanic gases and rock fragments (tephra).

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.