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Outcrop of Bishop Tuff from the Long Valley Caldera in California

Detailed Description

USGS geoscientists examine air fall tephra and pyroclastic flow deposits at the base of the Bishop Tuff, in a quarry near Bishop, CA. This pumice-rich tuff was laid down by the caldera-forming eruption of the Long Valley Caldera around 760,000 years ago.


Public Domain.

USGS photo by Jessica L. Ball