Newberry Volcano is the largest volcano in the Cascades volcanic arc and covers an area the size of Rhode Island (about 3100 km2 or 1200 mi2). 


Unlike familiar cone-shaped Cascades volcanoes, Newberry was built into the shape of a broad shield by repeated eruptions over the past 400,000 years. Throughout its eruptive history, Newberry has produced ash and tephra, pyroclastic flows, and lava flows that range in composition from basalt to rhyolite. About 75,000 years ago a major explosive eruption and collapse event created a large volcanic depression at its summit that now hosts two caldera lakes. Newberry last erupted about 1,300 years ago, and present-day hot springs and geologically young lava flows indicate that it is still an active volcano.


Date published: August 27, 2019

New names at Newberry drawn from CalVO geologist's mapping

In June 2019, the U.S. Board on Geographic Names approved twenty-five new formal geographic names at Newberry Volcano in central Oregon. The names were proposed by Julie Donnelly-Nolan, a Research Geologist with the Volcano Science Center of the USGS in Menlo Park, CA.

Date published: December 18, 2013

Lake-ice quakes observed at Newberry Volcano

Aided by record-setting subfreezing temperatures, the popping and cracking of ice in the caldera's lakes is picked up by local seismic stations.

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