Vents in the surface of the Earth through which magma and associated gases erupt; also, the forms or structures, usually conical, that are produced by the erupted material. [Glossary of Geology, 4th ed.]
Alexandria Digital Library Feature Type Thesaurus
Mount St. Helens lidar [ More info] Poster available in two sizes for downloading and printing.
Mount St. Helens, 1980 to now--what's going on? [ More info] Summarizes the eruptions of this spectacular volcano and the consequences for the surrounding landscape, explains how volcanoes like this form, and how we monitor their activity to mitigate hazards they pose.
Photo gallery of the Long Valley area, California [ More info] Selection of photographic images of the Long Valley area that illustrate the consequences of the past geologic history of the Sierra Nevada, Long Valley Caldera, the Mono-Inyo Craters volcanic chain, glaciation, and faulting.
Potential hazards from future volcanic eruptions in the Long Valley -- Mono Lake Area, California [ More info] An introduction to the volcano hazards in the Long Valley area based on the past geologic history of the Long Valley Caldera and the Mono-Inyo Craters volcanic chain.
Selected volcano information [ More info] Selected books, maps, videos, and other materials produced by the USGS Volcano Hazards Program. Many products highlighted here are intended for general audiences.
Sutter Buttes-the lone volcano in California's Great Valley [ More info] Explains history and structure of this unusual geologic feature.
The California Volcano Observatory: monitoring the state's restless volcanoes [ More info] Summarizes where, when, how often volcanoes erupt in California, and explains how our monitoring of these features helps people avoid the hazards that they pose.
The ongoing Pu'u 'O'o eruption of Kilauea Volcano, Hawai'i -- 30 years of eruptive activity [ More info] Fact sheet chronicles and illustrates Kilauea Volcano's longest rift-zone eruption in more than 500 years.
The story of the Hawaiian Volcano Observatory -- A remarkable first 100 years of tracking eruptions and earthquakes [ More info] History of the Hawaiian Volcano Observatory (HVO), established in 1912, including an overview of Hawaiian volcanic processes and USGS monitoring techniques.
This dynamic planet: World map of volcanoes, earthquakes, impact craters, and plate tectonics [ More info] Online world map with booklet (PDF format) giving an account of plate tectonics, volcanology, earthquake activity, and impact craters.
Alphabetical Index of Topics
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