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Images related to natural hazards.
Volcanic threat is defined as the qualitative risk of a volcano to people and property that might be impacted by specific volcanic hazards.
Volcanic threat is defined as the qualitative risk of a volcano to people and property that might be impacted by specific volcanic hazards.
USGS scientist David Ponce measuring gravity using a gravimeter along the Hayward-Rodgers Creek fault zone just north of San Pablo Bay, California.
USGS scientist David Ponce measuring gravity using a gravimeter along the Hayward-Rodgers Creek fault zone just north of San Pablo Bay, California.
In September 2014, during one of many community meetings held in Pāhoa to address concerns about Kīlauea Volcano's June 27th lava flow, USGS Hawaiian Volcano Observatory scientist Kevan Kamibayashi points out the flow's advance as of that week.
In September 2014, during one of many community meetings held in Pāhoa to address concerns about Kīlauea Volcano's June 27th lava flow, USGS Hawaiian Volcano Observatory scientist Kevan Kamibayashi points out the flow's advance as of that week.
C1 and C3 are granitic crystal-melt mush (partially crystallized magma) columns that fed the most recent Mono Craters eruptions. The connection from C1 to South Coulée (SC) is older and colder than the connection from C3 to North Coulée (NC) and Panum Crater (PC), which carries hydrothermal fluid to the surface.
C1 and C3 are granitic crystal-melt mush (partially crystallized magma) columns that fed the most recent Mono Craters eruptions. The connection from C1 to South Coulée (SC) is older and colder than the connection from C3 to North Coulée (NC) and Panum Crater (PC), which carries hydrothermal fluid to the surface.
USGS scientists Kevin Denton (left), Katherine “Kyeti” Morgan, and David Ponce set up a magnetic base station during fieldwork along the Hayward-Rodgers Creek fault zone in wheat fields north of San Pablo Bay.
USGS scientists Kevin Denton (left), Katherine “Kyeti” Morgan, and David Ponce set up a magnetic base station during fieldwork along the Hayward-Rodgers Creek fault zone in wheat fields north of San Pablo Bay.
A time-lapse camera located in HVO's observation tower captured these interesting images of Halema‘uma‘u during an intense lightning storm at Kīlauea's summit on October 16. Image captured at 11:36 PM.
A time-lapse camera located in HVO's observation tower captured these interesting images of Halema‘uma‘u during an intense lightning storm at Kīlauea's summit on October 16. Image captured at 11:36 PM.
Image captured at 11:43 PM.
This map shows recent changes to Kīlauea's active East Rift Zone lava flow field. The area of the flow on September 30 is shown in pink, while widening and advancement of the flow as of October 23 (based on satellite imagery and ground mapping) is shown in red. The yellow lines show the active lava tube system.
This map shows recent changes to Kīlauea's active East Rift Zone lava flow field. The area of the flow on September 30 is shown in pink, while widening and advancement of the flow as of October 23 (based on satellite imagery and ground mapping) is shown in red. The yellow lines show the active lava tube system.
An HVO geologist collects a sample of active lava for chemical analysis. The lava is quenched with water in the metal bucket.
An HVO geologist collects a sample of active lava for chemical analysis. The lava is quenched with water in the metal bucket.
This small-scale map shows Kīlauea's active East Rift Zone lava flow in relation to the eastern part of the Island of Hawai‘i. The area of the flow on September 30 is shown in pink, while widening and advancement of the flow as of October 23 is shown in red. The yellow lines show the active lava tube system.
This small-scale map shows Kīlauea's active East Rift Zone lava flow in relation to the eastern part of the Island of Hawai‘i. The area of the flow on September 30 is shown in pink, while widening and advancement of the flow as of October 23 is shown in red. The yellow lines show the active lava tube system.
This photo looks west towards the upper East Rift Zone of Kīlauea. The fume-filled crater at Pu‘u ‘Ō‘ō is in the foreground, and the vent for the June 27th lava flow is just out of view of the lower right corner of the photo. Mauna Loa is visible in the upper right.
This photo looks west towards the upper East Rift Zone of Kīlauea. The fume-filled crater at Pu‘u ‘Ō‘ō is in the foreground, and the vent for the June 27th lava flow is just out of view of the lower right corner of the photo. Mauna Loa is visible in the upper right.
A hornito was active in the upper portion of the June 27th flow, with hissing and jetting sounds coming from a small opening at the top. The hornito here was about 2.5 m (8 feet) tall. A hornito is formed by gas and lava forced through a small opening in the roof of a lava tube.
A hornito was active in the upper portion of the June 27th flow, with hissing and jetting sounds coming from a small opening at the top. The hornito here was about 2.5 m (8 feet) tall. A hornito is formed by gas and lava forced through a small opening in the roof of a lava tube.
A small channel feeds a lobe of pāhoehoe lava on the eastern margin of the June 27th flow. Scattered breakouts like these were active on the flow field today, with the farthest active lava about 6.4 km (4 miles) from the vent on Pu‘u ‘Ō‘ō.
A small channel feeds a lobe of pāhoehoe lava on the eastern margin of the June 27th flow. Scattered breakouts like these were active on the flow field today, with the farthest active lava about 6.4 km (4 miles) from the vent on Pu‘u ‘Ō‘ō.
The oxygen-regulated benthic flux chamber measures fluxes of water and chemical species across the sediment water interface. It is shown here deployed in the subtidal discharge zone in Indian River Bay, DE, USA
The oxygen-regulated benthic flux chamber measures fluxes of water and chemical species across the sediment water interface. It is shown here deployed in the subtidal discharge zone in Indian River Bay, DE, USA
Volcano Disaster Assistance Program staff members share skills, experience, and resources with the USGS VHP, a cooperation that supports the mission of both programs.
Volcano Disaster Assistance Program staff members share skills, experience, and resources with the USGS VHP, a cooperation that supports the mission of both programs.
Debris flow in channel near Butte Camp, Mount St. Helens, Washington.
Debris flow in channel near Butte Camp, Mount St. Helens, Washington.
Kalama Springs, Washington.
Kalama Springs, Washington.
Path of small debris flows originating above Butte Camp, Mount St. Helens, Washington.
Path of small debris flows originating above Butte Camp, Mount St. Helens, Washington.
To construct a geologic map of this area, USGS Hawaiian Volcano Observatory geologists initially used lava flow type, rock colors, and relative stratigraphic positions to distinguish between individual lava flows, and then relied on laboratory analyses and age-dates of the flows to refine their field mapping. USGS photo.
To construct a geologic map of this area, USGS Hawaiian Volcano Observatory geologists initially used lava flow type, rock colors, and relative stratigraphic positions to distinguish between individual lava flows, and then relied on laboratory analyses and age-dates of the flows to refine their field mapping. USGS photo.
An HVO field geologist must make his way through dense forest to map the full extent of an old Mauna Loa lava flow. USGS photo.
An HVO field geologist must make his way through dense forest to map the full extent of an old Mauna Loa lava flow. USGS photo.
Summit deflation over the past day was associated with the summit lava lake level slowly dropping. When this happens, collapses commonly occur within the Overlook crater. Solidified lava, attached to the Overlook crater walls, collapsed into the lake on several occasions today, triggering small dust plumes and agitation of the lake surface.
Summit deflation over the past day was associated with the summit lava lake level slowly dropping. When this happens, collapses commonly occur within the Overlook crater. Solidified lava, attached to the Overlook crater walls, collapsed into the lake on several occasions today, triggering small dust plumes and agitation of the lake surface.