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Images of Clear Lake Volcanic Field.
Geologists often break off the weathered surfaces of rocks in the field to get at the fresh, clean cores. This makes it easier to see the original mineralogy of the rock in question without oxidation, alteration, or other environmental impacts. USGS photo by D. Blatter
Geologists often break off the weathered surfaces of rocks in the field to get at the fresh, clean cores. This makes it easier to see the original mineralogy of the rock in question without oxidation, alteration, or other environmental impacts. USGS photo by D. Blatter
These freshly excavated boulders along Spruce Grove Road are basalt, which is an iron and magnesium-rich rock that’s fairly uncommon in the Clear Lake Volcanic Field.
These freshly excavated boulders along Spruce Grove Road are basalt, which is an iron and magnesium-rich rock that’s fairly uncommon in the Clear Lake Volcanic Field.
Eruption episode 3 is the most voluminous in the history of the Clear Lake Volcanic Field. Episode 3 rocks are of intermediate composition, primarily dacite, and make up many of the topographic high points in the field, including Mt. Konocti, where this photo is taken.
Eruption episode 3 is the most voluminous in the history of the Clear Lake Volcanic Field. Episode 3 rocks are of intermediate composition, primarily dacite, and make up many of the topographic high points in the field, including Mt. Konocti, where this photo is taken.
Cinder cones (or scoria cones) are relatively small, steep-sided volcanoes that are constructed around a single vent when lava is ejected into the air, breaks into smaller pieces, and builds up around the sides of the vent. This photo is looking across the quarry which exposes the interior of a cinder cone east of Clearlake Oaks in the Clear Lake Volcanic Field.
Cinder cones (or scoria cones) are relatively small, steep-sided volcanoes that are constructed around a single vent when lava is ejected into the air, breaks into smaller pieces, and builds up around the sides of the vent. This photo is looking across the quarry which exposes the interior of a cinder cone east of Clearlake Oaks in the Clear Lake Volcanic Field.
Located at the midpoint of Clear Lake in Lake County, California, Buckingham Peninsula shows evidence of young explosive volcanism in the Clear Lake Volcanic Field. Little Borax Lake, enclosed within the Buckingham golf course, is a water-filled maar crater, as is Horseshoe Bay to its northeast. USGS photo by J. Ball.
Located at the midpoint of Clear Lake in Lake County, California, Buckingham Peninsula shows evidence of young explosive volcanism in the Clear Lake Volcanic Field. Little Borax Lake, enclosed within the Buckingham golf course, is a water-filled maar crater, as is Horseshoe Bay to its northeast. USGS photo by J. Ball.
Thurston Lake and Mount Konocti, Clear Lake Volcanic Field, California.
Thurston Lake and Mount Konocti, Clear Lake Volcanic Field, California.
Mount Konocti as seen from the town of Clear Lake.
Mount Konocti as seen from the town of Clear Lake.
Clear Lake Volcanic Field, California. Tuff deposit outcrop.
Clear Lake Volcanic Field, California. Tuff deposit outcrop.
USGS scientists Deb Bergfeld and Laura Clor collect samples of the gas from the old Gas Hill wellhead in Kelseyville, CA. USGS photo by Jen Lewicki.
USGS scientists Deb Bergfeld and Laura Clor collect samples of the gas from the old Gas Hill wellhead in Kelseyville, CA. USGS photo by Jen Lewicki.
Mt. Konocti erupted during the most recent stage of volcanism (01. Ma to 10,000 years ago), and a future eruption from the same site would be devastating to the nearby inhabitants.
Mt. Konocti erupted during the most recent stage of volcanism (01. Ma to 10,000 years ago), and a future eruption from the same site would be devastating to the nearby inhabitants.
Mount Konocti, the most distinct volcanic feature of the Clear Lake Volcanics as viewed to the west from Cinder Cone.
Mount Konocti, the most distinct volcanic feature of the Clear Lake Volcanics as viewed to the west from Cinder Cone.
Mount Konocti, a mostly dacitic composite cone, on the western shore of Clear Lake, California. Thurston Lake is in the foreground.
Mount Konocti, a mostly dacitic composite cone, on the western shore of Clear Lake, California. Thurston Lake is in the foreground.
Photograph of men at the Kelseyville Gas Wells, ca.1910, by M. Rieder. Courtesy of California Historical Society Collection, University of Southern California Digital Libraries.
Photograph of men at the Kelseyville Gas Wells, ca.1910, by M. Rieder. Courtesy of California Historical Society Collection, University of Southern California Digital Libraries.