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Pyroclastic Flows are Rare, but Potentially Destructive, at Newberry

By Newberry

Eruptions of hot ash, pumice, and gas formed a pyroclastic flow deposit 75,000 years ago that can be seen at the base of the cliffs of Paulina Creek Falls.

The youngest of these types of deposits is the approximately 1,300 year old Paulina Lake pyroclastic flow. Two campgrounds are located on that deposit, which can be found along the southern shore of Paulina Lake. These infrequent but extraordinarily hot and fast moving flows would travel quickly down the slopes of Newberry and be very destructive.

Ash-flow tuff outcrop, northwest flanks of Newberry Volcano, Oregon...
Sources/Usage: Public Domain.
Larger dark lava bombs were carried in the pyroclastic flow supported within the ashy matrix (Credit: Donnelly-Nolan, Julie M.. Public domain.)
Ash-flow tuff outcrop on the northwest flanks of Newberry Volcano, ...
Sources/Usage: Public Domain.
Weathering has eroded the deposit into rounded mounds. Hammer hanging from outcrop in foreground is present for scale. (Credit: Donnelly-Nolan, Julie M.. Public domain.)