A Geoscience Digital Image Library

TitleView from the summit of Lassen Peak, California
DescriptionLassen Peak is a stratovolcano with a summit lava dome. It is in California, at the southern end of the Cascade Range, in Lassen Volcanic National Park. Major explosive eruptions occurred, beginning in May 1914, and continuing through 1917. Minor activity lasted until 1921. Lassen’s major eruptions were violent and were accompanied by pyroclastic flows and mudflows. All of Lassen’s rocks are andesite and dacite. Lava flows are found in some places, but most of Lassen’s deposits were airfall or mudflows. They range from fine ash beds to coarse and jumbled agglomerates. Besides Lassen, Mt. St. Helens is the only other Cascade volcano to erupt in the 20th century. The trail up to Lassen Peak begins with dusty switchbacks up the southeastern spine of the dormant volcano. It begins at just over 8000 feet, rises to the summit at about 10,500 feet, is five miles long and takes several hours to complete.
Geologic provinceCascade Mountains
LocationUSA ▹ California ▹ Shasta. Near Redding. Lassen Volcanic National Park.
PhotographerDexter Perkins. 2001-04-04.
Key wordsLassen, stratovolcano, California, dacite, andesite
Tech details416 KB. Vista. Canon Eos Rebel, 55mm lens, Fuji Sensia 100.
GeoDIL number287