Images

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.

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.

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.

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.

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.

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.

USGS-CVO building sign, Vancouver, Washington.

Geologic Map of Three Sisters Volcanic Cluster, Cascade Range, Oregon

South Sister northwest flank. Right shoulder at skyline is thin sheet of mafic material from 22ka summit eruption. Red cinders in headwall cirques are layered with dipping lava flows.

Geologic Map of the Washougal Quadrangle, Clark County, Washington and Multnomah County, Oregon (Scientific Investigation Map 3257).

Eruption of Soufriere Hills, Montserrat, November 2009

Map showing global ash and aviation encounters

Bariloche sand filters

Postshield eruption are the fourth stage of a Hawaiian volcano's evolution. A cap of evolved magma erupts to cover the surface of the volcano. Not all volcanoes have evidence for this phase.

Rejuvenated stage volcanism occurs after the volcano has moved away from the mantle hot spot. Eruptions occur in sporadic locations and may be interspersed with long periods of erosion.

Examples of seismograms of different types of earthquakes and tremor (constant ground shaking) recorded in Hawai‘i.

Michael Poland, Scientist-in-Charge of the Yellowstone Volcano Observatory.

An American exchange participant views the former hospital in Amero where the entire first floor was buried by lahars from Nevado del Ruiz (the second floor is visible).