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A hoodoo (also called a tent rock, fairy chimney, and 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 , 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. ==Occurrence== 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. Hoodoos are a tourist attraction in the Cappadocia region of Turkey, where houses have been carved from these formations. These rock formations were depicted on the reverse of the Turkish 50 new lira banknote of 2005–2009. In French, they are called ''demoiselles coiffées'' ("ladies with hairdos") or ''cheminées de fées'' ("fairy chimneys") and a number of them are found in the Alpes-de-Haute-Provence; one of the best-known examples is the formation called Demoiselles Coiffées de Pontis. Đavolja Varoš (Devil's Town) hoodoos in Serbia feature 202 exotic formations described as earth pyramids or "towers", as the locals refer to them. Since 1959, Đavolja Varoš has been protected by the state. It was also a nominee in the New Seven Wonders of Nature campaign. The hoodoo stones on the northern coast of Taiwan are unusual for their coastal setting. The stones formed as the seabed rose rapidly out of the ocean during the Miocene epoch. Efforts have been made to slow the erosion in the case of iconic specimens in Wanli. Hoodoos in Drumheller, Alberta, are a distinctive feature that continues to attract thousands of visitors each year. The sediments comprising these hoodoos formed between 70 and 75 million years ago during the Cretaceous Period as clay and sand sediments from the Horseshoe Canyon Formation were deposited. These hoodoos are able to maintain a unique mushroom-like appearance as the underlying base erodes at a faster rate compared to the capstones, a rate of nearly one centimeter per year, faster than most geologic structures. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hoodoo (geology)」の詳細全文を読む スポンサード リンク
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