Images

Top: Photograph of the SO2 camera installation when scientists tested the radio link to the Hawaiian Volcano Observatory (HVO). The camera is aimed at the plume emitting from the Overlook Crater, about 1.4 km away. Under typical trade wind conditions, the plume is blown to the southwest, thus moving from right to left in the imagery.

Vent activity, typical of that in summer and fall 1969 between episodes of high fountaining. The spattering is from one of two compartments that contained lava. Typically lava levels in the two compartments were different, and gas pistons might work in both but at different times.

Map showing area covered by lava flows of Mauna Ulu eruption. Note that the map was made in 1997, before diacritical marks were being used in Hawaiian place names. The two colors designate the 1969-71 and 1972-1974 parts of the eruption, respectively. In the scale, 3 km is equal to about 2 mi.

Seismic hazard across the State of Hawaii, with high seismic hazards depicted with warm colors (red-orange) and relatively low seismic hazards depicted with cool colors (green). Engineers use these types of maps to prescribe building codes known as Seismic Design Codes (SDC) and create earthquake resistant structures.

Seismic station locations (red triangles) on the Island of Hawai‘i and across the State of Hawaii (inset).

HVO seismologists use this to review automatically generated earthquake parameters (location, depth, magnitude), measure P- and S-wave arrival times, and re-compute earthquake hypocenter and magnitudes for cataloging and distribution to the public.

Although numerous intensity scales have been developed over the last several hundred years to evaluate the effects of earthquakes, the one currently used in the United States is the Modified Mercalli Intensity (MMI) Scale. It was developed in 1931 by the American seismologists Harry Wood and Frank Neumann.

Earthquakes near the Island of Hawai‘i between 1970-2006 with magnitude greater than 2.5. A (top left): locations of shallow earthquakes 0-22 km (0-14 mi) depth. B (top right): locations of deep earthquakes 22-55 km depth (14-34 mi). Bottom (C): cross section showing the depths of earthquakes in the rectangle in figure B.

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

Field-trip guide to Columbia River flood basalts, associated rhyolites, and diverse post-plume volcanism in eastern Oregon available at https://pubs.er.usgs.gov/publication/sir20175022O.

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).

American and Colombian exchange participants among the ruins in Amero, which was destroyed by an eruption of Nevado del Ruiz in 1985.

Village of Belalcázar along the Páez River in Colombia. Photograph taken in 2006 - note river bank vegetation and soccer pitch is restored in 12 years after 1994 lahar.

Panoramic image of Belacázar Village eight years after the 2008 lahar innundation. Lahar deposits in the foreground of the town are now soccer fields and a dirt bike track.

U.S. and Chilean scientists prepare for a research flight during the 2008 VDAP eruption response at Chaitén.

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

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

Mount Rainier 2018 Teacher Workshop

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.

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.

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