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Newberry may appear to be a sleeping volcano, but it is doing what volcanoes normally do by maintaining long periods of quiet that are punctuated by occasional eruptions.


The southwest portion of Newberry Caldera as seen from the air. Bi...
The southwest portion of Newberry Caldera as seen from the air. Big Obsidian flow stands out against the trees with Paulina Peak in the background. (Credit: Scott, William. Public domain.)

Future eruptions at Newberry Volcano will probably resemble those that occurred in the past 15,000 years. These volcanic eruptions varied from relatively quiet effusion of lava flows to highly explosive discharge of pumice and ash. Flank eruptions would most likely be basaltic lava flows or fountains of spatter and tephra that would build cinder cones. The caldera would be the site of most rhyolitic eruptions, which could include effusive lava flows (like Big Obsidian Flow) or explosive eruptions of tephra. The presence of lakes add to the danger of eruptions in the caldera. When magmamixes water, the result can produce highly explosive eruption.

Newberry is an area of active research. By more closely monitoring the volcano, and conducting field research to understand past eruptions, scientists can help to inform nearby communities when there is evidence of volcanic unrest, and can advise on the likely courses of events.