Images

Brimstone Basin, Yellowstone, aerial photo with overlay of two types of altered ground (light blue and pale pink shading) and locations of gas measurements (red dots). 2012 study

Geologic Hazards at Volcanoes (click for larger version)

Mount Scott Lookout seismic and GPS volcano monitoring station, view from the southwest. Near Crater Lake, Oregon.

Deformation monitoring equipment—GPS antenna maintenance on south side of Crater Lake National Park Boathouse on Wizard Island. Oregon

Oblique aerial photograph of source areas and runout paths of some of the devastating debris flows that were responsible for more than 20,000 fatalities in Vargas state, Venezuela, December 1999.

Lava-flow hazard zones map, Island of Hawai‘i. See Full Map for complete legend.

Sampling gas and taking temperature measurements from a fumarole at the summit of Mount Rainier, Washington.

Slope map of Mauna Loa, including lava flows erupted since 1823 (gray), showing the approximate number of hours or days it took for a flow to advance from the vent location to the ocean or maximum reach of a flow. One flow that moved down the steep slopes on west flank of Mauna Loa reached the ocean in as little as 3 hours after the vent started erupting in 1950.

Pyroclastic flow (dense darker grey billowing mass) travels down slope of Mayon volcano, Philippines while ash column rises from the vent. Dilute, lighter-colored ash billows off leading edge.

Map of hazard zones for ground fractures and "small-scale" subsidence for the Island of Hawai‘i. Subsidence and fracturing events are frequent in zone 1, which covers the summit and rift zones of Kīlauea and Mauna Loa volcanoes, but are somewhat less frequent in zone 2, on the south flank of Kīlauea.

The older or original suggested location of this rift is shown with a blue dashed line. Black arrows show one possibility for the westward migration of the Nīnole Hills rift to the location of Mauna Loa's current Southwest Rift Zone (yellow dashed line). The South Kona Slump and ‘Ālika-1 and ‘Ālika-2 landslides are shown off the west coast of the island.

Aerial view of Haleakalā Crater northward to Ko‘olau Gap. Sharp rimmed crater in near ground is Ka Lu‘u o ka ‘Ō‘ō.

Top panel shows a continuous GPS station located in Yellowstone National Park. The antenna is secured to the ground by several metal poles, and a nearby set of solar panels provides power to the station. Lower panel shows a semipermanent GPS station, with a small solar array for power and an antenna located close to the ground.

Researchers map the bottom of Castle Lake, near Mount St. Helens. For three days, researchers ran a small boat over the lake surface equipped with an acoustic Doppler current profiler (ADCP). The ADCP bounces an acoustic wave off the bottom that is reflected back to a mobile receiver in the boat.

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 Hood dominates the skyline outside of Portland, Oregon on a clear day. An major eruption of Mount Hood would pose a great hazard to the regional economy.

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.

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.

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.

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