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Volcano Hazard Program images.
Colors ranging from pink to purple indicate the water depth around the islands, while shades of gray show land topography above sea level. Red areas on the Island of Hawai‘i indicate lava flows erupted within the past 200 years.
Colors ranging from pink to purple indicate the water depth around the islands, while shades of gray show land topography above sea level. Red areas on the Island of Hawai‘i indicate lava flows erupted within the past 200 years.
Preview image for video: The lava lake in the Overlook crater, within Halema‘uma‘u Crater at Kīlauea's summit, undergoes frequent periods of spattering. The spattering is normally at the lake margins, and the surface crust often flows towards, and is consumed at, the spattering source.
Preview image for video: The lava lake in the Overlook crater, within Halema‘uma‘u Crater at Kīlauea's summit, undergoes frequent periods of spattering. The spattering is normally at the lake margins, and the surface crust often flows towards, and is consumed at, the spattering source.
A photograph of Mount St. Helens, as viewed from Elk Rock on January 18, 2014.
A photograph of Mount St. Helens, as viewed from Elk Rock on January 18, 2014.
Mount Rainier volcano looms over Puyallup Valley, near Orting, Washington.
Mount Rainier volcano looms over Puyallup Valley, near Orting, Washington.
Mount Rainier volcano looms over Puyallup Valley, near Orting, Washington.
Mount Rainier volcano looms over Puyallup Valley, near Orting, Washington.
Scientists conduct a stream channel cross-section survey of the Toutle River on the north side of Mount St. Helens (view to the southwest).
Scientists conduct a stream channel cross-section survey of the Toutle River on the north side of Mount St. Helens (view to the southwest).
Colors ranging from red to purple indicate the water depth around the Island of Hawai‘i, while shades of gray show land topography above sea level. Red shows lava flows erupted over the past 200 years. The Puna Ridge represents the submarine extension of Kīlauea's east rift zone.
Colors ranging from red to purple indicate the water depth around the Island of Hawai‘i, while shades of gray show land topography above sea level. Red shows lava flows erupted over the past 200 years. The Puna Ridge represents the submarine extension of Kīlauea's east rift zone.
The Kahauale‘a 2 flow remains active northeast of Pu‘u ‘Ō‘ō, with the flow front this week consisting of a narrow finger that has reached 7.5 km (4.7 miles) northeast of the vent on Pu‘u ‘Ō‘ō. The flow front has cut a narrow swath through the forest, and is igniting numerous small fires.
The Kahauale‘a 2 flow remains active northeast of Pu‘u ‘Ō‘ō, with the flow front this week consisting of a narrow finger that has reached 7.5 km (4.7 miles) northeast of the vent on Pu‘u ‘Ō‘ō. The flow front has cut a narrow swath through the forest, and is igniting numerous small fires.
Map showing the submarine shape of the Hawaiian hotspot track, which extends from the Hawaiian Islands, through a prominent bend in the middle of the Pacific Ocean, to Alaska's Aleutian Islands. The inset shows the volcanoes in the main Hawaiian Islands.
Map showing the submarine shape of the Hawaiian hotspot track, which extends from the Hawaiian Islands, through a prominent bend in the middle of the Pacific Ocean, to Alaska's Aleutian Islands. The inset shows the volcanoes in the main Hawaiian Islands.
View of Pu‘u ‘Ō‘ō, looking southwest. The vent for the Kahauale‘a 2 flow is on the near side of the crater, close to the center of the photograph (but obscured by white fume).
View of Pu‘u ‘Ō‘ō, looking southwest. The vent for the Kahauale‘a 2 flow is on the near side of the crater, close to the center of the photograph (but obscured by white fume).
The Kahauale‘a 2 flow remains active northeast of Pu‘u ‘Ō‘ō, with the flow front this week consisting of a narrow finger that has reached 7.5 km (4.7 miles) northeast of the vent on Pu‘u ‘Ō‘ō. The flow front has cut a narrow swath through the forest, and is igniting numerous small fires.
The Kahauale‘a 2 flow remains active northeast of Pu‘u ‘Ō‘ō, with the flow front this week consisting of a narrow finger that has reached 7.5 km (4.7 miles) northeast of the vent on Pu‘u ‘Ō‘ō. The flow front has cut a narrow swath through the forest, and is igniting numerous small fires.
During the first few hours of the Kamoamoa fissure eruption in March 2011, lava bubbled to the surface through a ground crack that propagated along Kīlauea Volcano's East Rift Zone. How it and other Hawaiian fissure eruptions work will be the topic of a talk at UH-Hilo on January 16, 2014.
During the first few hours of the Kamoamoa fissure eruption in March 2011, lava bubbled to the surface through a ground crack that propagated along Kīlauea Volcano's East Rift Zone. How it and other Hawaiian fissure eruptions work will be the topic of a talk at UH-Hilo on January 16, 2014.
Erupting vents on Mauna Loa's Northeast Rift Zone near Pu‘u‘Ula‘ula (Red Hill) on Mar. 25, 1984—just hours after the eruption began—sent massive ‘A‘ā lava flows moving toward Hilo at 4 miles per hour. By the time the eruption ended on April 15, lava flows had reached to within four miles of Hilo city limits. USGS photo.
Erupting vents on Mauna Loa's Northeast Rift Zone near Pu‘u‘Ula‘ula (Red Hill) on Mar. 25, 1984—just hours after the eruption began—sent massive ‘A‘ā lava flows moving toward Hilo at 4 miles per hour. By the time the eruption ended on April 15, lava flows had reached to within four miles of Hilo city limits. USGS photo.
Hawaiian Volcano Observatory seismologists will talk about Hawaii's history of destructive earthquakes in two public presentations. Paul Okubo (right) will speak at the University of Hawai‘i at Hilo on November 20, and Wes Thelen (left) will speak in Hawai‘i Volcanoes National Park on November 26.
Hawaiian Volcano Observatory seismologists will talk about Hawaii's history of destructive earthquakes in two public presentations. Paul Okubo (right) will speak at the University of Hawai‘i at Hilo on November 20, and Wes Thelen (left) will speak in Hawai‘i Volcanoes National Park on November 26.
Map of Mount St. Helens Crater Glacier created from LiDAR data acquired September 2009.
Map of Mount St. Helens Crater Glacier created from LiDAR data acquired September 2009.
CalVO geologist Mae Marcaida examines thin layers of volcanic ash sandwiched between thick beds of sediment deposited by ancestral Mono Lake in eastern California. Each ash layer is evidence of a past explosive eruption of the Mono Craters, which began erupting about 65,000 years ago just south of present-day Mono Lake.
CalVO geologist Mae Marcaida examines thin layers of volcanic ash sandwiched between thick beds of sediment deposited by ancestral Mono Lake in eastern California. Each ash layer is evidence of a past explosive eruption of the Mono Craters, which began erupting about 65,000 years ago just south of present-day Mono Lake.
The seismic records or waveforms are from two seismic stations, and show the highly repetitive and similar nature of the seismic events.
The seismic records or waveforms are from two seismic stations, and show the highly repetitive and similar nature of the seismic events.
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: 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.
In left foreground, ice-ravaged mafic edifice Little Brother is separated from North Sister by Little Ice Age trough of Collier Glacier. Both North Sister and Little Brother expose numerous oxidized scoria falls, whereas smooth black Middle Sister cone is cloaked by mafic lava flows.
In left foreground, ice-ravaged mafic edifice Little Brother is separated from North Sister by Little Ice Age trough of Collier Glacier. Both North Sister and Little Brother expose numerous oxidized scoria falls, whereas smooth black Middle Sister cone is cloaked by mafic lava flows.
Trout Lake lowland view from the south, downslope from Mount Adams, Washington. The lowland area along the White Salmon River (trees) is underlain by lahar deposits 300 and 6000 years old.
Trout Lake lowland view from the south, downslope from Mount Adams, Washington. The lowland area along the White Salmon River (trees) is underlain by lahar deposits 300 and 6000 years old.
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.
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.