Volcanic ash layers in rock. Cross-bedded layers of volcanic ash laid down during countless eruptions over thousands of years. The volcanoes that laid

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Volcanic ash layers in rock. Cross-bedded layers of volcanic ash laid down during countless eruptions over thousands of years. The volcanoes that laid down this ash are part of the Cascade Mountain Range. Studying the ash layers can help date the rocks and the eruptions, and help uncover the ancient history of the area. Photographed in the Columbia River Gorge, Washington State, USA.

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Size: 5356px × 3592px
Photo credit: © KAJ R. SVENSSON/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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