Remembering the May 18, 1980 Mount St. Helens Eruption...

Located in Skamania County, Washington, Mount St. Helens is part of the Cascade Volcanic Arc in the Pacific Northwest of the United State. As part of the Cascade Range, this mountain has a long recorded history of eruptive activity.

In March of 1980, an enormous bulge began to appear on the north side of Mount St. Helens, which was accompanied by small earthquakes. On May 18 at 8:32 a.m., an earthquake one mile below the mountain and measuring 5.1 on the Richter scale shook over 1300-feet off the peak, leaving a crater approximately 2000 feet deep, and sending a plume of ash 15 miles into the atmosphere. The following debris avalanches buried over 230 square miles of forest in a 150-foot deep mud. An estimated 12 million salmon, 7000 big game, and 57 people were killed, including USGS Field Geologist David Johnston who was working at an observation station during the eruption. In 1982 the 110,000-acre National Volcanic Monument was established at Mount St. Helen for natural preservation, research, recreation, and education.

In 2004, Mount St. Helens once again experienced several deep earthquakes sending a plume of ash into the air. With its continued tremors and dome building, the mountain has remained one of the most active volcanoes in North America. Although some believe that the future eruptions will not be nearly as catastrophic as the 1980 blast, Mount St. Helens continues to be a great challenge for scientists.

To learn more about the Mount St. Helens past eruptions and its current activity, visit the USGS Cascades Volcano Observatory at the following URL:
http://vulcan.wr.usgs.gov/home.html

To view more USGS images of the 1980 eruption, click on the following URL:
http://libraryphoto.cr.usgs.gov/cgi-bin/search.cgi?search_mode=exact&selection=Mount+St.+Helens%7CMount+St.+Helens

To find and purchase USGS research and ongoing studies on Mount St. Helen, visit the USGS Publications Warehouse at the link provided below:
http://pubs.er.usgs.gov/usgspubs/index.jsp?jboEventVo=PubResultView&view=basic&jboEvent=Search&pxfield_all=Mount+St.+Helen