Michael Poland

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.

Benchmark C9, installed by the US Coast and Geodetic Survey (now the National Geodetic Survey) in 1923 near Apollinaris Spring in Yellowstone National Park.  The number stamped into the mark, “7337.580,” is the elevation in feet that was determined by surveys the year the benchmark was established.  USGS photo by Michael Poland, September 4, 2024.

New steam vent at the base of a hill north of Nymph Lake, west of the highway and between Norris Geyser Basin and Roaring Mountain. USGS photo by Mike Poland, September 1, 2024.

Photo of dead trees along the edge of Nuphar Lake.  The white staining at the base of the trees is a telltale sign that the trees were immersed in thermal water containing silica.  USGS photo by Mike Poland, September 1, 2024.

Plot of size versus annual probability for hydrothermal explosion craters in Yellowstone National Park. The line is a model based on the energy required to form a crater of a specific size, and it is fit to known hydrothermal explosion craters in Yellowstone National Park.

Aerial view of Biscuit Basin, Yellowstone National Park, showing debris deposited by the July 23, 2024, hydrothermal explosion from Black Diamond Pool.  Major features are labeled.  The main debris field (within dashed yellow line) has a gray appearance.  Photo taken by Joe Bueter, Yellowstone National Park, on July 23, 2024.

Map of major thermal features in Biscuit Basin, Yellowstone National Park.  Base map from Google Earth

This animation shows a map of of Yellowstone seismicity by year from 2017 through 2023.  Earthquakes are red circles, with the circle size indicating earthquake magnitude.  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.

Infographic giving earthquake, deformation, thermal emission, and geyser statistics for the Yellowstone region for the year 2023.  The graphic accompanies the Yellowstone Volcano Observatory 2023 annual report, freely available online athttps://pubs.usgs.gov/publication/cir1524.

Front cover of the Yellowstone Volcano Observatory 2023 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 athttps://pubs.usgs.gov/publication/cir1524.

Site of April 15, 2024, hydrothermal explosion on Porcelain Terrace, Norris Geyser Basin, Yellowstone National Park.  The small crater and disrupted ground are in silica sinter deposits that formed in the past two years, since water has been flowing from the terrace into Nuphar Lake (off photo to right), and angular fragments of ejecta on top of the sinter are