Over the long term and geologic time, volcanic eruptions and related processes have directly and indirectly benefited mankind. Volcanic materials ultimately break down and weather to form some of the most fertile soils on Earth, cultivation of which has...
The major peaks in the US part of the Cascade Range are (from north to south) Mount Baker, Glacier Peak, Mount Rainier, Mount St. Helens, Mount Hood, Mount Adams, Mount Jefferson, Three Sisters, Newberry Volcano, Crater Lake, Mount McLoughlin, Medicine...
The principal volcanoes of the Hawaii Islands (from northwest (oldest) to southeast (youngest)) are Niihau, Kauai, Oahu, Molokai, Lanai, Maui, Kahoolawe, and Hawaii (Big Island).
Several lofty volcanic peaks dominate the Cascade Range of the Pacific Northwest; the principal part of the range extends from Mount Garibaldi in British Columbia, Canada, to Lassen Peak in northern California, a distance of about 1000 miles.  Sources of...
Debris flows pose the greatest hazard to people near Mount Rainier. A debris flow is a mixture of mud and rock debris that looks and behaves like flowing concrete. Giant debris flows sometimes develop when large masses of weak, water-saturated rock slide...
There are many paths to becoming a volcanologist. Most share a college or graduate school education in a scientific or technical field, but the range of specialties is very large. Training in geology, geophysics, geochemistry, biology, biochemistry,...
Mount St. Helens, Washington 2004-2007: Volcanic dome growth renewed on September 20, 2004 and has been continuous. The dome has more than doubled its size in this 3-year period. See USGS third anniversary activity facts for more information. 1980-1986:...
The largest eruption in the world this century occurred in 1912 at Novarupta on the Alaska Peninsula. An estimated 15 cubic kilometers of magma was explosively erupted during 60 hours beginning on June 6 -- (which is equivalent to 230 years of eruption...
The May 18, 1980 eruption of Mount St. Helens (Washington) was the most destructive in the history of the United States. Novarupta (Katmai) Volcano , Alaska, erupted considerably more material in 1912, but owing to the isolation and sparse population of...
The most recent eruptive activity occurred at Lassen Peak (California) in 1914-1917 A.D. This eruptive episode began on May 30, 1914, when a small phreatic eruption occurred at a new vent near the summit of the peak. More than 150 explosions of various...