Images

Time series of vertical displacements during April–October 2017 at four GPS stations (LAK1, LAK2, LKWY, and SEDG) on the north side of Yellowstone Lake. Downward trends indicate subsidence and upward trends show uplift. Uplift “spikes” in late September are related to inclement weather and do not show true deformation. Error bars are one standard deviation.

Field crew from Oregon State University and University of Wisconsin-Madison install a magnetotelluric site within Yellowstone National Park. 

Map of gravity stations measured in 2017 in Yellowstone National Park. Yellow lines are roads, dashed line marks the caldera boundary, black line outlines Yellowstone National Park, green circles note resurgent domes, and red dots are gravity stations.

Example Hydrotherm output. Hydrotherm is a three-dimensional simulation of multiphase groundwater flow and heat transport in the temperature range of 0 to 1200 degrees Celsius and the pressure range of 1 to 1000 MPa.

WorldView-2 natural-color satellite image from December 9, 2017, showing thermal areas as snow-free zones on the north side of Mallard Lake resurgent dome in Yellowstone National Park.

A blue glow is emitted by radiation during operation of the USGS TRIGA® Reactor, a low-power nuclear research reactor in Denver, Colorado. Photo by Christopher Farwell, October 27, 2017.

Echinus Geyser in eruption on October 24, 2017.  Photo by MA Bellingham, used with permission.

Sunset lake in Black Sand Basin of Yellowstone National Park

Iron Spring Creek winds through Black Sand Basin in Yellowstone National Park.  Cliff Geyser, in eruption, is in the middle ground.  USGS photo by Mike Poland, October 19, 2017.

View of the Silver Gate landslide complex from Bunsen Peak in Yellowstone National Park.  The landslide originates from Terrace Mountain.

A weir constructed by Irving Friedman and Dan Norton to measure water discharge and to monitor changes in hydrothermal activity on a tributary flowing into Boundary Creek in southwest Yellowstone National Park. USGS photo by Shaul Hurwitz, September 17, 2017.

Focal mechanism determined by moment tensor analysis, which uses a model to fit the long-period (~10 s period or greater) ground motion records recorded at multiple locations.

Inverted funnel connected to thermoplastic tubing used to collect gas from a hot spring pool near Lassen Peak, California.

A newly emerged adult wetsalts tiger beetle. Photo by Robert K. D. Peterson, 2017.

Equipment for measuring carbon dioxide and methane emissions used to monitor changes at Steamboat Geyser in 2019. The white cylinder is the chamber, which is lowered to the ground. Gases emitted from the ground surface accumulate in the chamber. An instrument in the cart continuously measures gas concentrations and carbon isotope compositions.

Upright petrified tree in Yellowstone National Park. 

Amphitheater Mountain and Soda Butte Creek viewed from the Yellowstone National Park northeast entrance road. 

Fishing Cone, a small thermal feature near the shore of the West Thumb of Yellowstone Lake.

Hikers on Mount Everts near Mammoth Hot Springs, Yellowstone National Park.

Panoramic of the West Yellowstone rhyolite lava flow taken along Highway 20 (between the West entrance of Yellowstone National Park and Madison Junction). The flow is approximately 111,000 years old and has a volume of about 41 km³ (10 mi³). 

A geologist examples a basaltic lava flow along the Madison River, looking for an area that can yield samples suitable for ⁴⁰Ar/³⁹Ar geochronology.  USGS photo by Jorge Vazquez, June 2017.