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The Ohanapecosh Formation at Chinook Pass, WA.

Detailed Description

The Ohanapecosh Formation at Chinook Pass (foreground), intruded by a large sill associated with the Miocene Tatoosh pluton; Mount Rainier in the background. Cover photo for SIR 2017-5022-B (pubs.er.usgs.gov/publication/sir20175022B).