321010 - 321070 
(was 1201)
David A. Johnston Cascades Volcano Observatory
U.S. Geological Survey
1300 SE Cardinal Court, Building 10, Suite 100
Vancouver, Washington 98683

Telephone :

(360) 993-8910
(360) 601-8310 cell

Telefax :

(360) 993-8981

Scientist in Charge:

Seth Moran

Email :

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Website :


Pacific Northwest Seismic Network website:


Building manager: Edward C.Brown Email:

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Geologist/VDAP: Angie Diefenbach Email:

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The David A. Johnston Cascades Volcano Observatory (CVO) is dedicated to our colleague, David Johnston, who was killed on May 18, 1980, at Mount St Helens.  St. Helens is visible from CVO and is located about 70 km north-northeast.  CVO, one of five volcano observatories supported by the USGS Volcano Hazards Program, houses about 60 scientists, technicians, and support personnel from the US Geological Survey (USGS) and one field engineer from the Pacific Northwest Seismograph Network.  In addition, scientists from other USGS observatories and especially the USGS office in Menlo Park, California, carry out volcano studies in the Cascade Range.

The primary duties of the Observatory are to conduct geologic, hydrologic and geophysical studies related to monitoring, understanding of processes, and assessment of hazards at potentially active volcanoes in Washington, Oregon, and California. The Pacific Northwest Seismograph Network (PNSN), which operates on a cooperative agreement between USGS and the University of Washington, provides continuous seismic monitoring of the Cascade Range in Washington and Oregon, and the USGS Northern California Seismic Network in Menlo Park, California, provides continuous seismic monitoring of the Cascade Range in northern California. Several groups of specialists at CVO work cooperatively with the other USGS observatories to operate or assist with geodetic, gas-emission, and landslide-related projects.  In addition, CVO is home to the Volcano Disaster Assistance Program (VDAP), a joint program of the Office of Foreign Disaster Assistance of U.S. Agency for International Development and USGS.  VDAP maintains a cache of volcano-monitoring instruments and expertise to respond to volcanic crises in foreign countries, as requested by hosts and approved by OFDA, and to help selected countries develop institutions to monitor volcanoes and assess hazards.

CVO facilities include laboratories for Geographic Information Systems; design, testing, and fabrication of monitoring equipment; sediment concentration and particle size; gas geochemistry and maintenance of airborne instruments; and petrology.  In addition, experimental facilities at CVO investigate landslide and flowage processes and volcanic interactions with snow and ice. The USGS-CVO Debris-Flow Flume at the H.J. Andrews Experimental Forest east of Eugene, Oregon, provides a laboratory for study of landslide and debris-flow processes at scales of up to 10 m3.

The Scientist in Charge (SIC) is responsible for issuing information statements and alerts of potentially hazardous volcanic and hydrologic events. The SIC and scientific staff members work with land managers such as the U.S. Forest Service and National Park Service and State and local emergency management agencies to provide information to concerned recipients, including local, State, and Federal agencies, and private corporations with major nearby operations. The news media receive the same information and issue it to the public. Staff members are designated to respond to official and media inquiries.

Several staff members have major responsibility for outreach and public education, although most observatory staff members participate at some level with public agencies, schools, and civic organizations to educate citizens and public officials about volcano hazards and risk mitigation.  Groups of CVO scientists work closely with teams of concerned agencies to develop emergency-response plans to potential unrest and eruptions at Cascade volcanic centers.