article: Mount St. Helens
links: Portland, Oregon American football Cascade Range Columbia River Ronald Reagan Cascade Volcanoes Seattle Cowlitz River Washington Gifford Pinchot National Forest Idaho United States Geological Survey Cascade Volcanic Arc Japan Native American United States Richter scale Seattle, Washington 1980 eruption of Mount St. Helens Vesuvius Klickitat Earth's mantle Mount Fuji Tectonic plate Magma U.S. state Richter magnitude scale Skamania County, Washington Mass media Anno Domini United States Congress Ring of Fire Volcanic Explosivity Index