Cliff
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- This article is about the geological formation. For other uses, see Cliff (disambiguation)
In geography, a cliff is a significant vertical, or near vertical, rock exposure. Cliffs are categorized as erosion landforms due to the processes of erosion and weathering that produce them. Cliffs are common on coasts, in mountainous areas, escarpments and along rivers. Cliffs are usually formed by rock that is resistant to erosion and weathering. Sedimentary rocks most likely to form cliffs are sandstone, limestone, chalk, and dolomite. Igneous rocks, such as granite and basalt also often form cliffs.
An escarpment (or scarp) is a type of cliff, formed by the movement of a geologic fault, or a landslide.
Most cliffs have some form of talus slope at their base. In arid areas or under high cliffs, these are generally exposed jumbles of fallen rock. In areas of higher moisture, a soil slope may obscure the talus.
Many cliffs also feature waterfalls or rock shelters. Sometimes a cliff peters out at the end of a ridge, with tea tables or other types of rock columns remaining.
Given that a cliff need not be exactly vertical, there can be ambiguity about whether a given slope is a cliff or not, and also about how much of a certain slope to count as a cliff. (For example, given a truly vertical rock wall above a very steep slope, one could count only the rock wall, or the combination.) This makes listings of cliffs an inherently uncertain endeavor.
According to some sources, the highest cliff in the world, about 1,340 m high, is the east face of Great Trango in the Karakoram mountains of northern Pakistan. (This uses a fairly stringent notion of cliff, as the 1,340m figure refers to a nearly vertical headwall; adding in a very steep approach brings the total height to over 1,600m.) The highest sea cliffs, 1,010 m high, are located at Kalaupapa, Hawaii. (This uses a less stringent definition, as the average slope of these cliffs is about 1.7, corresponding to an angle of 60 degrees.)
Considering a truly vertical drop, Mount Thor on Baffin Island in Arctic Canada is the highest at 1,370m (4,500 ft) high in total (the top 480 m (1,600 ft) is overhanging). This is said to give it the longest purely vertical drop on Earth at 1,250 m (4,100 ft).
Large or famous cliffs
The following is an incomplete list of cliffs of the world.Asia
Above SeaAbove Land
- Trango Towers in Baltoro Muztagh, Pakistan, the highest cliffs in the world
- Uli Biaho Towers, Pakistan, near Trango Towers
- Baintha Brakk (The Ogre), Panmah Muztagh, Pakistan
- Latok Group, near Baintha Brakk
- Various cliffs in the Ak-Su Valley of Kyrgyzstan
Europe
Above Sea- Cape Enniberg, Faroe Islands, 750 m above North Sea
- Croaghaun, Achill Island, Ireland, 668 m above Atlantic Ocean
- Preikestolen, Norway, 604 m above Lysefjorden
- Slieve League, Ireland, 601 m above Atlantic Ocean
- Cabo Girão, Madeira, 589 m above Atlantic Ocean
- Beachy Head, England, 162 m above the English Channel
- Cliffs of Moher, Ireland, 120 m above Atlantic Ocean
- White cliffs of Dover, England, 100 m above the Strait of Dover
- Troll Wall, Norway 1100 m above base
- Kazalnica Mięguszowiecka, Tatra Mountains, Poland 576 m above the Czarny Staw pod Rysami
- Mały Kieżmarski Szczyt (north face), Tatra Mountains, Slovakia about 900 meters denivelation (vertical rise)
- Giewont (north face), Tatra Mountains, Poland, 852 meters above Polana Strążyska glade
North America
- El Capitan, Yosemite Valley, Sierra Nevada, California, United States; about 900 m (3,000 ft) high
- Northwest Face of Half Dome, near El Capitan; 1,340m (4,400 ft) total, vertical portion about 610 m (2,000 ft)
- All faces of Devil's Tower, Wyoming, United States
- Various faces of Shiprock, New Mexico, United States
- The North Face of North Twin Peak, Rocky Mountains, Alberta, Canada
- Mount Thor, Baffin Island, Canada; 1,370m (4,500 ft) total; top 480 m (1,600 ft) is overhanging. This reputedly gives it the largest purely vertical drop on Earth at 1,250 m (4,100 ft).
- Mount Asgard, Baffin Island
Greenland
- Nalumasortoq, Tasermiut Fjord, Greenland; over 800m high
South America
- Auyan Tepui (Angel Falls), about 1000m (the falls are 979m, the highest in the world)
- All faces of Cerro Torre, Patagonia, Chile-Argentina
- All faces of Cerro Chalten (Fitz Roy), Patagonia, Argentina
- Various faces of the Torres del Paine group, Patagonia, Chile
References
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