Images

Simplified Geologic Map of Yellowstone, modified from USGS I-711 by Marli Miller, University of Oregon. All rock material resulting from the major caldera-forming eruptions are labelled at Qt, where the dashed caldera boundary highlights the scale of these events. Older volcanic, sedimentary and metamorphic rocks are found outside of this boundary.

A Light Detection and Ranging (LiDAR) shaded relief image overlaid on an aerial imagery basemap. The Sulphur Hills, part of the Sour Creek Resurgent Dome, are visible in the upper half of the image, while the floodplain and meanders of Pelican Creek are visible at the bottom.

Geology of Yellowstone Map zoomed into the Lower Geyser Basin. This view shows a park-wide geologic map overlaid on a shaded relief layer from a digital elevation model. Red diamonds and black circles show geysers and gas sample locations, respectively.

Schematic diagram illustrating the difference between a main shock with aftershocks (top), a sequences of foreshocks, main shock, and aftershocks (middle), and a seismic swarm (bottom).  Adapted from manuscript by Farrell and others, 2009.

Map of earthquakes greater than M1.5 that occurred between March 1 and May 12, 2020, in the Intermountain West. The main shock-aftershock sequences in central Idaho and near Salt Lake City are labeled. Orange dots are earthquakes that occurred within 24 hours, and yellow 1 week, of the map being generated (May 12, 2020)

Archive view of the Yellowstone Volcano Observatory website in 2001.

Archive view of the Yellowstone Volcano Observatory website in 2009.

Mobile view of the Yellowstone Volcano Observatory website.

Ground fissure along the shore of Stanley Lake, Idaho, cause by liquefaction during shaking from the March 31, 2020, Stanley earthquake. Photo by Zach Lifton, Idaho Geological Survey, May 2020.

Submerged trees at the inlet delta of Stanley Lake, Idaho. Liquefaction during shaking from the March 31, 2020, Stanley earthquake caused ground subsidence and collapse of the delta. Photo by Zach Lifton, Idaho Geological Survey, May 2020.

Grand Prismatic Spring in Midway Geyser Basin Yellowstone National Park on October 19, 2017.

Sunset lake in Black Sand Basin of Yellowstone National Park

The relationship between Δ30 and N2/3He ratios in hydrothermal gases from Iceland and Yellowstone. Δ30 and N2/3He ratios are shown for samples collected from gases in Iceland (yellow circles) and Yellowstone (red circles). The Yellowstone mantle-endmember is arguably indistinguishable in terms of N2/3He from the convecting upper mantle (grey diamonds).

Highly sensitive instruments installed deep below the ground surface yield great records of earthquakes near and far. The March 31, 2020, magnitude 6.5 Stanley, Idaho, earthquake shows up very clearly in borehole strainmeter station B944's four different sensors.

For every major earthquake in the U.S., UNAVCO downloads high-rate data from all nearby GPS/GNSS stations. The downloads for the March 31, 2020, magnitude 6.5 Stanley, Idaho, earthquake include more than 20 stations in and around Yellowstone. Figure by Christine Puskas (UNAVCO).

Map of USGS “Did You Feel It?” reports for the March 31, 2020, M6.5 Stanley, Idaho, earthquake.  Taken from https://earthquake.usgs.gov/earthquakes/eventpage/us70008jr5/dyfi/intensity.

Imperial Geyser hot spring pool in Yellowstone National Park is about 30 m (about 100 ft) across and contains alkaline-Cl waters with a steam vent in the pool and mudpots outside the pool area (in the upper right part of this photo). USGS Photo by Pat Shanks, 2019.

Annie Carlson, Research Permitting Coordinator for Yellowstone National Park during 2017–2023, during a winter ski expedition in the park. National Park Service photo by Jon Nicholson, January 2020.

Sabrina Brown collecting samples from Yellowstone Lake core YL16-2C at the National Lacustrine Core Facility (LacCore) at the University of Minnesota.

Mineral stability diagram showing minerals that are stable under changing temperature and dissolved silica concentrations that are found at and just beneath the floor of Yellowstone Lake.  Two important points illustrated by this diagram are: (1) the minerals that are stable when reacted with vapor-dominated fluids (kaolinite, boehmite) differ substantially fro

Contrasting photos of Heart Spring on Geyser Hill in the Upper Geyser Basin from 1998 (left) and 2019 (right). Can you spot differences in the hot spring? Photos courtesy of the National Park Service.