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.]
Visual monitoring of volcanoes by closed-circuit television and video monitoring for a permanent video record of events using slow-scan television which permits continuous surveillance at a distance for remote volcanoes or in times of danger.
Volcano Watch is a weekly newsletter issued by the U.S. Geological Survey's Hawaiian Volcano Observatory on volcanic features on the Big Island, volcanic hazards, and informational topics of Long Valley, Montserrat, or Alaska.
Homepage of the Yellowstone Volcano Observatory with links to information about the observatory at Yellowstone National Park, volcanic history, photo gallery, monitoring data, publications and products, and Frequently Asked Questions (FAQs).