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Volcano Hazard Program images.
Graph shows thickness of ash (and larger-sized particles within 20-40 km) that fell to the ground downwind of Mount St. Helens during the eruption on May 18, 1980. The volcano ejected a minimum of 1.1 km3 of uncompacted tephra, which is equivalent to 0.20-0.25 km3 of magma or solid rock.
Graph shows thickness of ash (and larger-sized particles within 20-40 km) that fell to the ground downwind of Mount St. Helens during the eruption on May 18, 1980. The volcano ejected a minimum of 1.1 km3 of uncompacted tephra, which is equivalent to 0.20-0.25 km3 of magma or solid rock.
Heavy ashfall (20-30 mm) from Tungurahua, Ecuador, 2006.
Heavy ashfall (20-30 mm) from Tungurahua, Ecuador, 2006.
Dusting of Klyuchevskoy ash on camera bag, 2006.
Dusting of Klyuchevskoy ash on camera bag, 2006.
Geologic Hazards at Volcanoes. To download the full poster click here.
Geologic Hazards at Volcanoes. To download the full poster click here.
Mount Rainier Teacher Workshop Participants 2011
Mount Rainier Teacher Workshop Participants 2011
Columbian photographer Reid Blackburn's camera, recovered from the Mount St. Helens blast zone in 1980. The film in it was too damaged to yield images.
Columbian photographer Reid Blackburn's camera, recovered from the Mount St. Helens blast zone in 1980. The film in it was too damaged to yield images.
Lava-flow hazard zone map, Hawai‘i Island
Lava-flow hazard zone map, Hawai‘i Island
The station is a lahar monitoring station with a broadband seismometer and video camera. Data from the station use radio telemetry to send real time information to the Instituto Geofisico of Ecuador.
The station is a lahar monitoring station with a broadband seismometer and video camera. Data from the station use radio telemetry to send real time information to the Instituto Geofisico of Ecuador.
Pyroclastic flow cartoon depicting the flow moving down the slope of a volcano through a valley.
Pyroclastic flow cartoon depicting the flow moving down the slope of a volcano through a valley.
LOS = Line of Sight
Example of an event-tree schematic used when forecasting the probable scenarios that may play out in the event of volcanic unrest or eruption. Scenarios are updated as events unfold.
Example of an event-tree schematic used when forecasting the probable scenarios that may play out in the event of volcanic unrest or eruption. Scenarios are updated as events unfold.
Emergency response planning exercise for a volcanic event with Washington State and local government officials.
Emergency response planning exercise for a volcanic event with Washington State and local government officials.
Three images of crop damage, ash plume and cleanup for the homepage
Three images of crop damage, ash plume and cleanup for the homepage
Ashfall will cause accelerated wear and tear on sewage pump impellers (metal pitting and thinning).
Ashfall will cause accelerated wear and tear on sewage pump impellers (metal pitting and thinning).
Drill records have found traces of previously formed shorelines (strandlines) depressed below the current sea level - further evidence of subsidence due to the added weight of the volcano.
Drill records have found traces of previously formed shorelines (strandlines) depressed below the current sea level - further evidence of subsidence due to the added weight of the volcano.
American and Colombian exchange participants among the ruins in Amero, which was destroyed by an eruption of Nevado del Ruiz in 1985.
American and Colombian exchange participants among the ruins in Amero, which was destroyed by an eruption of Nevado del Ruiz in 1985.
Relative explosiveness and resulting height of eruption columns typically associated with different styles of eruption
Relative explosiveness and resulting height of eruption columns typically associated with different styles of eruption
Minor ashfall on hay field, Augustine eruption, Homer area, Alaska, 1986.
Minor ashfall on hay field, Augustine eruption, Homer area, Alaska, 1986.
Trace of Augustine ash on car hood, Homer, Alaska, January 2006.
Trace of Augustine ash on car hood, Homer, Alaska, January 2006.
White Salmon River (Washington) at USGS gauge site, 2.3 km downstream of Condit Dam, looking downstream: (a) 53 min before breaching; (b) 20 min after breaching, at discharge peak; (c) 76 min after breaching, at peak sediment concentration, with high water line evident; (d) ~2.5 h after breaching, discharge has returned to background and sediment concentration is f
White Salmon River (Washington) at USGS gauge site, 2.3 km downstream of Condit Dam, looking downstream: (a) 53 min before breaching; (b) 20 min after breaching, at discharge peak; (c) 76 min after breaching, at peak sediment concentration, with high water line evident; (d) ~2.5 h after breaching, discharge has returned to background and sediment concentration is f
Lahar devastation after the eruption of Mount Pinatubo, Philippines.
Lahar devastation after the eruption of Mount Pinatubo, Philippines.