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Pinnacles of volcanic breccia at Pinnacles National Park

By California Volcano Observatory
A broad orange and grey pyramid-shaped rock face contrasts with a clear blue sky, and sits among smaller spires and pillars of the same rocks. All are cut by deep cracks and depressions, and subtle angled layers are visible in the largest rock face. Their bases are surrounded by sagebrush and scrubby trees, and in the background is a low boulder-strewn hill of the same rocks.
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Detailed Description

Weathered rhyolite breccias form the spires, towers, and caves that characterize Pinnacles National Park. These relatively soft volcanic deposits are perched on harder, more resistant lavas and intrusions that make up the base of the volcanic field. 

Sources/Usage

Public Domain.