A Geoscience Digital Image Library

TitleExfoliation Flakes on El Capitan, Yosemite Valley, California
DescriptionThis view shows several exfoliation flakes half way up El Capitan, a granitic monolith in Yosemite Valley, California. The large flake in the lower center part of the photo is called Texas Flake, because of its shape. A smaller flake above it is called Boot Flake; there is a rock climber sitting on top of Boot Flake. Exfoliation to produce flakes of this sort is common when plutons from deep in the Earth reach the surface. The release of confining pressure leads to jointing and slabs eventually fall off. The rock shown here, called the El Capitan Granite, is of Cretaceous age. The picture also shows many younger light colored dikes cutting across the El Capitan granite.
Geologic provinceSierra Nevada
LocationUSA ▹ California ▹ Merced. Near Merced. Yosemite Valley National Park.
PhotographerDexter Perkins. 2002-02-21.
Key wordsYosemite, granite, exfoliation, El Capitan
Tech details774 KB. Vista.
GeoDIL number2448