A Geoscience Digital Image Library
A Geoscience Digital Image Library
| Title | View of Half Dome above the Merced River, Yosemite Valley, California |
|---|---|
| Description | The rounded peak with the cliff face (center of photo) is Half Dome. It towers more than 1,250 meters (4,000 ft) above the floor of Yosemite Valley, and is made up of the Half Dome Granodiorite (86-88 Ma), part of the Tuolumne Intrusive Suite. The rounded dome on the left in this photo is North Dome, and below it (in shadow above trees) is the Royal Arches. Half dome was one of the few peaks in the vicinity that was not completely covered by Pleistocene glaciers. The rounded summit is the result of exfoliation (sheet jointing), caused as rock cracked in sheets parallel to the surface of the exposed granite. A vertical joint (fracture) system led to formation of the sheer northwest face. The rock of the “missing half” (more like a missing quarter) of Half Dome was quarried away by glaciers that passed along the base of the cliff. Boulders of the Half Dome granodiorite can be found throughout the valley downstream. |
| Location | USA ▹ California. Near Merced. Yosemite National Park. |
| Photographer | Dexter Perkins. 2002-02-21. |
| Key words | Yosemite, Half Dome, granodiorite, glacier, exfoliation |
| Tech details | 979 KB. Vista. Canon A1, Agfachrome 100. |
| GeoDIL number | 2435 |
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