Labels: unusual rock
Southwest face of El Capitan from Yosemite Valley
|Elevation||7,569 feet (2,307 m)|
|Topo map||USGS El Capitan|
|Age of rock||Cretaceous|
El Capitan is a 3,000-foot (910 m) vertical rock formation in Yosemite National Park, located on the north side of Yosemite Valley, near its western end. The granite monolith is one of the world's favorite challenges for rock climbers.
The formation was named "El Capitan" by the Mariposa Battalion when it explored the valley in 1851. El Capitan ("the captain", "the chief") was taken to be a loose Spanish translation of the local Native American name for the cliff, variously transcribed as "To-to-kon oo-lah" or "To-tock-ah-noo-lah". It is unclear if the Native American name referred to a specific Tribal chief, or simply meant "the chief" or "rock chief". In modern times, the formation's name is often contracted to "El Cap", especially among rock climbers.
The top of El Capitan can be reached by hiking out of Yosemite Valley on the trail next to Yosemite Falls, then proceeding west. For climbers, the challenge is to climb up the sheer granite face; there are dozens of named climbing routes, all of them long and difficult.
El Capitan is composed almost entirely of El Capitan Granite, a pale, coarse-grained granite emplaced approximately 100 mya (million years ago). In addition to El Capitan, this granite forms most of the rock features of the western portions of Yosemite Valley. A separate intrusion of igneous rock, the Taft Granite, forms the uppermost portions of the cliff face. A third igneous rock, diorite, is present as dark-veined intrusions through both kinds of granite.
Along with most of the other rock formations of Yosemite Valley, El Capitan was carved by glacial action. Several periods of glaciation have occurred in the Sierra Nevada, but the Sherwin Glaciation, which lasted from approximately 1.3 mya to 1 mya, is considered to be responsible for the majority of the sculpting. The El Capitan Granite is relatively free of joints, and as a result the glacial ice did not erode the rock face as much as other, more jointed, rocks nearby.
Labels: el capitan
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