Images

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.

A view of White Mountain -- a deposit of the Heart Mountain detachment -- from the Sunlight Basin Road in Wyoming. Much of the evidence supporting the lamprophyre diatreme triggering mechanism theory for the landslide was gathered at White Mountain.

Yellowstone Lake bathymetry showing the location of the Deep Hole vent field.  Inset shows locations of heat-flux measurements (red dots) in the Deep Hole vent field.

Research Vessel Annie and Remotely Operated Vehicle Yogi.  a) R/V Annie on Yellowstone Lake operated by the Global Foundation for Ocean Exploration.  Image Rob Harris, OSU.  b) ROV Yogi with GFOE President Dave Lovalvo.  Image Todd Gregory, GFOE.  C) ROV Yogi and 1-m heat flow probe.  This pr

Site of the former Fountain Hotel in Yellowstone National Park.  Red arrows indicate the location of the pipe that ran through the meadow between Leather Pool and the site of the Fountain Hotel (yellow arrow). Yellowstone National Park photo by Annie Carlson, October 2021.

Wading across Salt River at Etna, streamgage 13027500, to collect samples

Interferogram created from data collected on September 22, 2020, and September 17, 2021, by the Sentinel-1 satellite system. Colored fringes indicate a change in distance (called range change) between the satellite and ground surface that is caused by surface deformation.

“Hey Bear” volcano, Wyoming, with Raggedtop Mountain in the background. Hey Bear volcano is a small scoria cone that is about 1.3 million years old and that erupted over Eocene (~50 million-year-old) rocks (noted by yellow dotted line). Photo by Matthew Brueseke, Kansas State University, August 2021, used with permission.

Muddy Creek near Dad streamgage, zero flow

Photograph of Twin Buttes in Lower Geyser Basin looking to the northwest, with Excelsior Geyser of Midway Geyser Basin in the foreground. Twin Buttes is a thermal kame that formed when glaciers covered the area, and hydrothermal activity below the ice led to melting and the deposition and cementation of glacial sediments.

The Yellowstone borehole geophysical network, installed by UNAVCO in 2007–2008. The placement of the boreholes is focused primarily around the caldera, and the boreholes contain a mix of instruments, including strainmeters, seismometers, tiltmeters, and pore pressure sensors.

Imperial Geyser, Lower Geyser Basin, Yellowstone National Park. USGS photo by Lauren Harrison, July 2021.

USGS scientists Laura Dobeck and Sara Peek carrying field equipment to set up a gas monitoring station in Yellowstone National Park. USGS photo by Jennifer Lewicki, July 13, 2021.

Little Snake River near Dixon low streamflow

Low Flows at Little Snake River near Dixon streamgage

Comparison of Porkchop Geyser in September 1984 (left) and August 1986 (right).  The Geyser entered a period of near-constant eruption in 1985, and the pool disappeared; it exploded on September 5, 1989.

View of Monument Geyser Basin in Yellowstone National Park, with one of the silica spire "monuments" (from which the basin gets its name) in the foreground. USGS photo by Mike Poland, May 15, 2021.

Roaring Mountain, an acid-sulfate thermal area about 5 miles south of Norris Geyser Basin along the Norris-Mammoth road.  At times during the late 1800s and early 1900s, the sound of gas escaping from vents could be heard over a mile away, but today the thermal area is mostly quiet, although remains intensely hot with over 100 megawatts of geothermal radiative

Photographs of the two dominant rock types found on Mount Everts: the Everts Formation (photo by Natali Kragh, May 18, 2021) and the Landslide Creek Formation (photo by Emma Kerins, May 2021). Notice the difference in scale between these two units, indicated by the pencil and field book.

Map of Yellowstone National Park showing the location of major travertine deposits. The green dashed line is the outline of Yellowstone Caldera and red lines are major paved roads.

Photographs of travertine in Yellowstone. A) Travertine terraces actively forming at Mammoth Hot Springs.