Images

Schematic cross section of the magmatic and hydrothermal systems underlying Yellowstone Caldera, showing magmatic volatiles emitted during crystallization of the rhyolitic magma and/or from basalt intrusions or convection, and the hypothesized relation with earthquake swarms on the caldera margins.  The exsolved fluids accumulate at lithostatic pressures in the

Frosted trees in the Fairy Falls area of Yellowstone National Park near the Firehole River.  National Park Service photo by Annie Carlson, 2014.

The contact (red arrow) between Huckleberry Ridge Tuff ignimbrite members A and B is marked by a time break of probably weeks to a month or so.

A mud pot in the Obsidian Pool Thermal Area, near Mud Volcano. The large amounts of suspended sediment make the thermal water much more viscous than pure water. Photo by Shaul Hurwitz, September 2014.

Example model output of possible ash distribution from a month-long Yellowstone supereruption. Results vary depending on wind and eruption conditions. Historical winds for January 2001 used here.

Beryl Spring's strongly boiling blue pool is about 8 m (25 ft) wide and contains high-chloride liquid water with a near-neutral pH. Immediately behind the pool is a loud, hissing fumarole producing a white cloud of steam. USGS Photo by Pat Shanks, 2002.

The left axis shows the number of earthquakes per week. The right axis is the total cumulative number of earthquakes, which means it has to always increase. It increased a lot in the period 1996-2003 when there was a period of uplift near Norris.

Station map showing seismograph stations used in the location of the M4.8 earthquake that occurred near Norris Geyser Basin on March 30, 2014.  The yellow star shows the earthquake epicenter.  Red triangles represent seismograph stations with a P-wave arrival pick.  Green triangles represent seismograph stations with both a P-wave and a S-wave arrival

Seismograms of the magnitude 4.8 earthquake that occurred in Yellowstone on March 30, 2014, as recorded by seismometers at station YNR near Norris Geyser Basin.  Top: Seismogram recorded on the accelerometer, which stayed on scale during the shaking.  Bottom: “Clipped” seismogram recorded on the broadband seismometer, which went off scale during the shakin

Telemetry system of the Yellowstone Seismic Network operated by the University of Utah Seismograph Stations.  Black arrows show analog telemetry and pink arrows show digital telemetry.  The green line is the boundary of Yellowstone National Park.

Record section showing horizontal component seismograms from stations in the Yellowstone region from the M4.8 earthquake that occurred near Norris Geyser Basin on March 30, 2014.  The vertical blue dashed line represents the origin time of the earthquake at 12:34:39.16 UTC.  The red line represents the P-wave arrival with a velocity of ~5.7 km/s.  The

3-component seismograms from station YHB for the M4.8 earthquake that occurred near Norris Geyser Basin on March 30, 2014, and showing the P-wave arrival pick (red) and the S-wave arrival pick (green) as determined by UUSS analysts.  The vertical blue dashed line represents the origin time of the earthquake at 12:34:39.16 UTC.

Time history of Yellowstone Caldera uplift (black line) and subsidence patterns along with quarterly catalog earthquake counts (blue bars). Note that large swarms in 1985 and 2010 accompany uplift to subsidence of caldera. The vertical deformation on the right axis was measured at the Sour Creek (SC) dome in the eastern part of the Yellowstone Caldera.

Top: Map of repeating earthquake areas corresponding to the deformation episodes, below. Bottom: Left 1996-1998 Yellowstone caldera uplift episode. Middle: 1998-2004 subsidence episode. Right: 2004-2010 uplift episode. Bottom: vertical ground deformation from GPS observations at station, WLWY, on the Sour Creek resurgent dome.

Top: Examples of some of the photos taken from helicopter over Mammoth Hot Springs in September 2013. Photos taken by Hank Heasler. Bottom: Hill-shade image calculated from the 2013 DEM over Mammoth Hot Springs and that was derived from a series of overlapping photos using Structure-from-Motion photogrammetry.

The seismic records or waveforms are from two seismic stations, and show the highly repetitive and similar nature of the seismic events.

Huckleberry Ridge Tuff deposit exposed on Mt. Everts, near the northern boundary of Yellowstone National Park. The deposit was created by ash falling from the plume early in the eruption sequence, 2.08 million years ago. Photo by Madison Myers, Montana State University.

Photo of the Old Faithful Inn lobby, which features a six-story-tall fireplace and chimney made from rocks quarried form a rhyolite lava flow in Yellowstone.  NPS photo by Jim Peaco, July 22, 2013.

Map of Yellowstone National Park showing Brimstone Basin and other areas known to release carbon dioxide from the ground.

YVO Webcam, October 27, 2012. Webcam overlooks Biscuit Basin in Yellowstone National Park.

View of ripples caused by wind winnowing of the Huckleberry Ridge Tuff fall deposits at Mount Everts. Other layers below show evidence for rain and hail landing with the falling ash. Scale in centimeters and inches.