Hoodoos

A hoodoo (also called a tent rock, fairy chimney or earth pyramid) is a tall, thin spire of rock that protrudes from the bottom of an arid drainage basin or badland. Hoodoos, which may range from 1.5 to 45 metres (4.9 to 147.6 ft), typically consist of relatively soft rock topped by harder, less easily eroded stone that protects each column from the elements. They generally form within sedimentary rock and volcanic rock formations.

Hoodoos are found mainly in the desert in dry, hot areas. In common usage, the difference between hoodoos and pinnacles (or spires) is that hoodoos have a variable thickness often described as having a "totem pole-shaped body". A spire, on the other hand, has a smoother profile or uniform thickness that tapers from the ground upward. An example of a single spire, as an earth pyramid, is found at Aultderg Burn, near Fochabers, Scotland.

Hoodoos range in size from the height of an average human to heights exceeding a 10-story building. Hoodoo shapes are affected by the erosional patterns of alternating hard and softer rock layers. Minerals deposited within different rock types cause hoodoos to have different colors throughout their height.

Hoodoos are commonly found in the High Plateaus region of the Colorado Plateau and in the Badlands regions of the Northern Great Plains (both in North America). While hoodoos are scattered throughout these areas, nowhere in the world are they as abundant as in the northern section of Bryce Canyon National Park, located in the U.S. state of Utah (see geology of the Bryce Canyon area). They are also very prominent a few hundred miles away at Goblin Valley State Park on the eastern side of the San Rafael Swell.

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