Images

Mount Hood in the not-so-far distance beyond Downtown Portland, Oregon. Photograph taken at the top of the Portland Aerial Tram line on Marquam Hill.

Geothermal ice cave at Mount Baker's summit formed by melting of a glacier due to increased heat from subsurface magma and fumarole on the surface expelling hot gasses.

Mount Bachelor viewed from the south. Sparks Lake and South Sister visible in the background. Oregon.

Mount Bachelor's east facing ski slopes at sunrise.

Glacier Peak volcano, Washington reflected in pond below the Whitechuck Glacier, view from the south in late summer.

Visible relief in the hillside exposure is about 800-900 ft. Dusty assemblage deposit occurred approximately between 5100 and 5500 yr B.P. Magma volume of >5 km3, which is a lot for what was probably one eruptive stage. The source lava dome is gone, apparently having disintegrated entirely during extrusion and subsequent glacial interaction.

Hualālai Volcano (center) above Kīholo Bay on Hawai‘i Island's West Coast is flanked by lava flow erupted from the volcano around 1800 (right) and 1859 Mauna Loa flow (left).

CalVO scientist Tom Sisson studies a lava flow in the Harrat Rahat Volcanic Field in Saudi Arabia for an international collaboration with the Saudi Geological Survey to conduct a seismic and volcanic hazard assessment for the volcanic field.

Simulated fractures and subsidence above a widening dike (dark area at bottom) were generated in a small-scale model using a box filled with flour, sugar, and corn meal. The simulated dike (tip is dark area bottom center of photograph) consisted of two linoleum sheets taped together.

Tiltmeters allowed 24-hour monitoring as the information was telemetered back to CVO. Other instruments such as displacement meters for measuring cracks, seismometers for measuring earthquakes, gas sensors for measuring gas concentrations, and magnetometers for measuring the magnetic field, were also used for 24-hour monitoring.

Locations (Lat, Long, Depth) of January 17, 2010, earthquake swarm on Madison Plateau, Yellowstone National Park.

Mammoth Hot Springs at Yellowstone National Park, Wyoming.

CalVO staff assembled in the Rambo Auditorium, Menlo Park, CA

Guardian Geyser and Norris Geyser Basin, Yellowstone National Park.

Magma forms above the subducting slab of oceanic crust and accumulates at the base of Earth's rigid crust before collecting in a storage zone 13 km (8 mi) beneath the volcano prior to eruption.

Due to the cataclysmic eruption of May 18, 1980, many of the locations annotated on this map are now either covered or no longer visible.

Non-volcanic peaks of the North Cascades lie in the background. Dusty Creek drainage experiences regular lahars. Gamma Ridge Formation are hydrothermally altered rocks on left ridge. Loose pyroclastic fill deposits cap right ridge; Eastern view, Glacier Peak, Washington.

Exposed rock ridges are thick Pleistocene lava flows that were confined between large glaciers. Glacier Peak, Washington, view north.

Information regarding volume and rates of advance for the crevassed Crater Glacier at Mount St. Helens, Washington, are extracted from Digital Elevation Models created from aerial photography. The red line shows the extent of Crater Glacier in 2012. Since 2012, the glacier has advanced about 50 m (160 ft) down the Loowit channel.

Summer geology intern Mindy Juergenson climbs over downed lodgepole pine trees killed in the fire of 1988 as she packs a GPS station out of the field (inset). Nine temporary stations are deployed each April/May and retrieved in October/November. The temporary stations supplement a network of permanent stations that record ground deformation data year-round.

Silica sinter (an amorphous form of silicon dioxide) forms from the waters that flow from hot springs near Shoshone Lake, Yellowstone National Park. USGS photograph by Jake Lowenstern.