Title | Lassen Peak, California, seen from the northeast |
Description | Lassen Peak is a stratovolcano with a summit lava dome. It is in California's Lassen Volcanic National Park, at the southern end of the Cascade Range. Major explosive eruptions occurred fromn May, 1914, 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. The soft rocks are highly erodible, as can be seen in this photograph. Besides Lassen, Mt. St. Helens is the only other Cascade volcano to erupt in the 20th century. |
Chronostratigraphy | recent |
Geologic province | Cascade Mountains |
Location | USA ▹ California ▹ Shasta. Near Redding. Lassen Volcanic National Park. |
Photographer | Dexter Perkins. 1990. |
Collection | E111014992F. |
Key words | Lassen, stratovolcano, California, dacite, andesite |
Tech details | 693 KB. Vista. Canon Eos Rebel, 55mm lens, Fuji Sensia 100. |
GeoDIL number | 280 |
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