Fact Sheet 2014–3119
Notice: This USGS Publication Supersedes USGS Fact Sheet 173-98
On May 22, 1915, a large explosive eruption at the summit of Lassen Peak, California, the southernmost active volcano in the Cascade Range, devastated nearby areas and rained volcanic ash as far away as 280 miles to the east. This explosion was the most powerful in a series of eruptions during 1914–17 that were the last to occur in the Cascade Range before the 1980 eruption of Mount St. Helens, Washington. A century after the Lassen eruptions, work by U.S. Geological Survey (USGS) scientists in cooperation with the National Park Service is shedding new light on these events.
First posted December 8, 2014
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Clynne, M.A., Christiansen, R.L., Stauffer, P.H., Hendley, J.W., II, and Bleick, H., 2014, A sight "fearfully grand"—Eruptions of Lassen Peak, California, 1914 to 1917: U.S. Geological Survey Fact Sheet 2014–3119, 4 p., https://dx.doi.org/10.3133/fs20143119.
ISSN 2327-6916 (print)
ISSN 2327-6932 (online)