Lava Creek Tuff
The Lava Creek Tuff is a tuff formation in Wyoming, created during the Lava Creek eruption around 630,000 years ago, which formed the Yellowstone Caldera.
The Lava Creek Tuff is distributed in a radial pattern around the caldera and is formed of 1,000 km3 (240 cu mi) of ignimbrites.
The tuff has been exposed by erosion at Tuff Cliff along the Gibbon River.
Lava Creek Tuff ranges in color from light gray to pale red in some locales. Rock texture of the tuff ranges from fine-grained to aphanitic and is densely welded. The maximum thickness of the tuff layer is approximately 180–200 m (590–660 ft).
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