Images

Flow chart illustrating the many variables influencing ash-induced insulator flashover.

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.

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.

Featured speaker from Colombia discusses lahars at Orting, Washington, event.

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

View of Mount Baker from the west. Summit area draped with aerial imagery from National Agriculture Imagery Program (NAIP) collected in September 2015. Digital topography from High-resolution digital elevation dataset for Mount Baker and vicinity, Washington, based on lidar surveys of 2015: U.S.

The USGS-Cascades Volcano Observatory opens its doors to the public on Saturday, May 12, for a one-day open house. Scientists will be on-hand from 10:00 am to 5:00 pm to share the results of their research and talk about volcano hazards. Hands-on activities and equipment demonstrations will be featured.

Mount Rainier 2018 Teacher Workshop

Scientists monitor data in the California Volcano Observatory operations room, Menlo Park, California.

Relative explosiveness and resulting height of eruption columns typically associated with different styles of eruption

Table of ash fall severities based on accumulated thickness.

Collapsed roofs after severe ashfall from Galunggung Volcano, West Java, Indonesia.

Dusting of Klyuchevskoy ash on camera bag, 2006.

Trace of Augustine ash on car hood, Homer, Alaska, January 2006.

Surveyor Frank Dodge's 1894 cross-section of Halema‘uma‘u overlaid on his 1892 cross-section. The 1892 lava lake was measured at 73 m (240 ft) below the rim of Halema‘uma‘u pit and by early-1894, the lava lake had filled the pit and frequently overflowed onto the caldera floor.

Photograph taken on March 20, 1894 looking up at the Halemaʻumaʻu lava lake perched atop a low dome on the floor of Kaluapele (Kīlauea caldera).

The painting by Jules Tavernier, depicting the 1880-81 lava flow from Mauna Loa as it enters a stream near Hilo, Hawaii on July 20, 1881, provided courtesy of the National Park Service, Hawaii Volcanoes National Park (catalog number HAVO 806).

Strong shaking during the 1868 Hayward Fault earthquake caused the second story of the Alameda County Courthouse in San Leandro to collapse (photo courtesy of the Bancroft Library, University of California). The inset photo shows the courthouse before the quake

Collapse sinkhole in a salt dome in Daisetta, Texas (September 2008). Salt is particularly susceptible to rapid dissolution causing large bowl-shaped sinkholes. Injection of fluids into this salt dome increased the dissolution of the salt causing a 60-foot deep sinkhole that covered several acres and destroyed many buildings.

Cover-collapse sinkhole in limestone near Frederick, Maryland (September 2003). Many sinkholes occur along highways where rainwater runoff is concentrated into storm drains and ditches increasing the rate of sinkhole development (note the sewer drain pipe beneath roadway).

Photo of Redoubt and vicinity taken from the gas/obs fixed-wing flight.