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California Volcano Observatory images.
Lassen Peak photographed from the Devastated Area about 4 hours before the explosive eruption of May 22, 1915.
Lassen Peak photographed from the Devastated Area about 4 hours before the explosive eruption of May 22, 1915.
Benjamin F. Loomis Historical Photograph Collection: Lost Creek drainage area covered in mud, rocks, and debris from a mudflow off Lassen Peak. Photo courtesy of NPS.
Benjamin F. Loomis Historical Photograph Collection: Lost Creek drainage area covered in mud, rocks, and debris from a mudflow off Lassen Peak. Photo courtesy of NPS.
Steam issuing from summit of Lassen Peak from head of Lost Creek following mudflow. "Hot Rock"(large boulder) in foreground. Photographs taken a few hours prior to second major eruption and hot blast.
Steam issuing from summit of Lassen Peak from head of Lost Creek following mudflow. "Hot Rock"(large boulder) in foreground. Photographs taken a few hours prior to second major eruption and hot blast.
Benjamin F. Loomis Historical Photograph Collection: Lassen Peak showing new lava flow on summit and large mudflows on slopes. Photo courtesy of NPS.
Benjamin F. Loomis Historical Photograph Collection: Lassen Peak showing new lava flow on summit and large mudflows on slopes. Photo courtesy of NPS.
A second view of Lassen Peak and the Deveastated Area following an explosive eruption and mudflowk. The crater of the volcano is visible, revealing that a lava dome which had previously been growing there was destroyed by the explosion. Subsequently, a lava flow began refilling the crater, and was mistakenly thought to have created the mudflow.
A second view of Lassen Peak and the Deveastated Area following an explosive eruption and mudflowk. The crater of the volcano is visible, revealing that a lava dome which had previously been growing there was destroyed by the explosion. Subsequently, a lava flow began refilling the crater, and was mistakenly thought to have created the mudflow.
Lassen Peak photographed from the Devastated Area prior to the 1914-1915 eruption that changed the landscape.
Lassen Peak photographed from the Devastated Area prior to the 1914-1915 eruption that changed the landscape.
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.
Horse-drawn carriage on road in Sisson, California, El Monte Hotel in foreground, Mount Shasta in the background. Image courtesy of the Library of Congress.
Horse-drawn carriage on road in Sisson, California, El Monte Hotel in foreground, Mount Shasta in the background. Image courtesy of the Library of Congress.
Photograph of the town of Sisson (later (1922) the town of Mt. Shasta) in the distance at the foot of Mount Shasta in winter. Snow covered fir trees in the foreground. Photo courtesy of University of Southern California Libraries and California Historical Society. Digitally reproduced by the USC Digital Library.
Photograph of the town of Sisson (later (1922) the town of Mt. Shasta) in the distance at the foot of Mount Shasta in winter. Snow covered fir trees in the foreground. Photo courtesy of University of Southern California Libraries and California Historical Society. Digitally reproduced by the USC Digital Library.
In a February 5, 2019 visit, USGS Director Jim Reilly was given a tour of CalVO facilities, including the Operations Room. Here Emily Montgomery-Brown explains the networks that monitor California's threatening volcanoes.
In a February 5, 2019 visit, USGS Director Jim Reilly was given a tour of CalVO facilities, including the Operations Room. Here Emily Montgomery-Brown explains the networks that monitor California's threatening volcanoes.
Infographic about the 2019 report "California's Exposure to Volcanic Hazards"
Infographic about the 2019 report "California's Exposure to Volcanic Hazards"