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# A Five-Mile-Deep Sandstone Bed in Leavenworth
- URL: https://www.cascadepbs.org/show/nick-rocks/episode/a-five-mile-deep-sandstone-bed-in-leavenworth-pgoghg/
- Published: 2025-12-23T22:01:30.000Z
- Updated: 2025-12-23T22:30:10.000Z
- Description: Leavenworth’s sandstone basin holds the key to a dramatic era of volcanic eruptions.
- Author: Cascade PBS Staff
- Tags: Nick on the Rocks, Season 7, Episode 3, #ZZZ_Episode_05f3c39f-9d4f-4063-a95e-6bd672a9b1a9, #episode, #ZZZ_Show_fb43f9d5-44f4-411a-854a-568025965642, #v1.16

The peaks that surround Leavenworth are granite, but the valley itself is an enormous sandstone basin built up over millennia. The discovery of an ancient layer of volcanic ash chronicles an era of eruptions and tectonic activity that rapidly created the sandstone and some unique outcrops around the Washington town.