Geologists as heroes

Last year, after backpacking for days through the bright white granitic rock in the high country of the Sierra Nevada, my friends and I began descending to our point of departure near Bishop, California. As we made our way down Piute Canyon, we began to see outcrops of sedimentary rock, weathered bluffs so red they might have been out of a Georgia O’Keefe painting. This startling contrast got me wondering how that red rock got there.

Sedimentary rock in the Sierra Nevada
Photo: T. Gething

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