campo volcánico 1439 m / 4,721 ft California, USA, 38.97°N / -122.77°W Current status: normal or dormant (1 out of 5)
Clear Lake volcanic field lies in the northern Coast Ranges, California, ca. 135 km north of San Francisco. The volcanic field consists of lava dome complexes, cinder cones, and maars of basaltic-to-rhyolitic composition. Mount Konocti, a dacitic lava dome on the south shore of Clear Lake, is the largest volcanic feature. The area has intense gethermal activity, caused by a large, still hot silicic magma chamber about 14 km wide and 7 km beneath the surface. It provides the heat source for the Geysers, the world's largest producing geothermal field on the SW side of the volcanic field. Its geothermal power plants can generate approximately 2000 megawatts, enough to power two cities the size of San Francisco. The latest volcanic activity happened about 10,000 years ago and formed maars and cinder cones along the shores of Clear Lake, the larges natural freshwater lake in California. Volcanism around Clear Lake is related to the complex San Andreas transform fault system.
Volcanic activity has been largely non-explosive, with the exception of one major explosive eruption that must have occurred and deposited a airfall tuff. Most lavas found here range from basalt through rhyolite in composition, dacite being the most dominant type.
Eruptions at Clear Lake volcanic field: 4 eruptive episodes separated by time gaps of ca. 150-200,000 years have been recognized: 2.1-1.3 million years ago (m.y.), 1.1-0.8 m.y., 0.65-0.30 m.y., and 100,000-10,000 years ago. The total volume of about 100 individual eruptions exceeds 70 cubic kilometers. Eruptive products from the first activity episode are found in the east of the field. The second activity episode constructed Cobb Mountain (1 million years, Ma) and Mount Hannah (0.9 Ma). The third episode of activity was at the Mount Konocti–Thurston Lake area, the most voluminous dacite and rhyolite feature of the Clear Lake volcanics. The most recent activity, up to about 10,000 years ago were small mostly basaltic and andesitic eruptions in the north of the field.
Sources: GVP, NCGS (Northern California Geological Society)
Walking & Study tours VolcanoDiscovery's signature tours for small groups: Discover volcanoes and volcanic areas from close with an expert in their field! These tours have a broad mix of activities and interests from photography, walking, study travel, nature & culture.
Pearl of the Aegean Santorini is one of the most beautiful islands in the world, famous for its breathtaking sea-filled caldera and picturesque villages. Discover its fascinating natural and cultural history on a relaxed walking study tour with us.
We truly love working to bring you the latest volcano and earthquake data from around the world. Maintaining our website and our free apps does require, however, considerable time and resources.
We need financing to increase hard- and software capacity as well as support our editor team. We're aiming to achieve uninterrupted service wherever an earthquake or volcano eruption unfolds, and your donations can make it happen! Every donation will be highly appreciated. If you find the information useful and would like to support our team in integrating further features, write great content, and in upgrading our soft- and hardware, please make a donation (PayPal or Online credit card payment).
Thanks to your past donations, these features have been added recently:
Earthquake archive from 1900 onwards
Additional seismic data sources
Improved content in English
Download and Upgrade the Volcanoes & Earthquakes app to get one of the fastest seismic and volcano alerts online: Android | IOS
Copyrights:VolcanoDiscovery y otras fuentes como se ha señalado. Uso de material: Most texts and images, in particular photographs, on this website are protected by copyright. Further reproduction and use of without authorization is usually not consented. If you are not sure or need licensing rights for photographs, for example for publications and commercial use, please contact us.