Cliff

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"Precipice" redirects here. For other uses, see Precipice (disambiguation).
"Rockface" redirects here. For the TV series, see Rockface (TV series).
For other uses, see Cliff (disambiguation).
The Trango Towers in Pakistan. Their vertical faces are the world's tallest cliffs. Trango Tower center; Trango Monk center left; Trango II far left; Great Trango right.
Europe's highest cliff, Troll wall in Norway. A famous BASE location for jumpers from around the world.

In geography and geology, a cliff is a vertical, or near vertical, rock exposure. Cliffs are formed 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 include 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 scree 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 tributary 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. Coastal erosion may lead to the formation of sea cliffs along a receding coastline.

The Ordnance Survey distinguishes between cliffs (continuous line along the top edge with projections down the face) and outcrops (continuous lines along lower edge).

The far southwestern aspect of Nanga Parbat's Rupal face, highest cliff (rock wall/mountain face) in the world. The steepest part of the face lies 2km to the northeast.

Large and famous cliffs[edit]

Cliffs near Sortavala, Russia
The Matengai in Oki Islands, Japan
Cliffs along the north shore of Isfjord, Svalbard, Norway.
Close-up view of Verona Rupes, a 20 km high fault scarp on Miranda, a moon of Uranus.[1]

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 just the rock wall, or the combination. This makes listings of cliffs an inherently uncertain endeavor.

Some of the largest cliffs on Earth are found underwater. For example, an 8,000-metre drop over a 4,250-metre span can be found at a ridge sitting inside the Kermadec Trench.

The highest cliff (rock wall, mountain face) in the world, is Nanga Parbat's Rupal Flank, which rises approximately 4,600 metres, or 15,000 feet, above its base. According to other 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 1,340 m figure refers to a nearly vertical headwall of two stacked pillars; adding in a very steep approach brings the total drop from the East Face precipice to the nearby Dunge Glacier to nearly 2,000 m.

The location of the world's highest sea cliffs depends also on the definition of 'cliff' that is used. Guinness World Records states it is Kalaupapa, Hawaii,[2] at 1,010 m high. Another contender is the north face of Mitre Peak, which drops 1683 metres to Milford Sound, New Zealand.[3] These are subject to a less stringent definition, as the average slope of these cliffs at Kaulapapa is about 1.7, corresponding to an angle of 60 degrees, and Mitre Peak is similar. A more vertical drop into the sea can be found at Maujit Qaqarssuasia (also known as the 'Thumbnail') which is situated in the Torssukátak fjord area at the very tip of South Greenland and drops 1,560 m near-vertically.[4]

Considering a truly vertical drop, Mount Thor on Baffin Island in Arctic Canada is often considered the highest at 1370 m (4500 ft) high in total (the top 480 m (1600 ft) is overhanging), and is said to give it the longest vertical drop on Earth at 1,250 m (4,100 ft). However, cliffs on Baffin Island, such as Polar Sun Spire, or others in remote areas of Greenland may be higher.

The highest cliff in the solar system may be Verona Rupes, an approximately 20 km (12 mi) high fault scarp on Miranda, a moon of Uranus.

The following is an incomplete list of cliffs of the world.

Asia[edit]

Above Sea

Above Land

Europe[edit]

Above sea

Above Land

North America[edit]

Mount Thor, Baffin Island, Nunavut, Canada, commonly regarded as the highest vertical drop on Earth
Southwest face of El Capitan from Yosemite Valley
The face of Notch Peak at sunset

Several big granite faces in the Arctic regions vie for the title of 'highest vertical drop on Earth', but reliable measurements are not always available. The possible contenders include (measurements are approximate):

Other notable cliffs include:

South America[edit]

Africa[edit]

Above Sea

Above Land

Oceania[edit]

Cliffsides near Beachlands, New Zealand in the Hauraki Gulf.

Above Sea

As habitat determinants[edit]

Cliff landforms provide unique habitat niches to a variety of plants and animals, whose preferences and needs are suited by the vertical geometry of this landform type. For example, a number of birds have decided affinities for choosing cliff locations for nesting,[10] often driven by the defensibility of these locations as well as absence of certain predators.

See also[edit]

References[edit]

  1. ^ "Natural world: the solar system: highest cliffs". Guinness World Records. Archived from the original on 2006-05-21. Retrieved 2006-08-05. 
  2. ^ "Highest Cliffs". Guinness World Records. Archived from the original on 2005-11-27. Retrieved 2006-05-02. 
  3. ^ The Encyclopedia of Tourism and Recreation in Marine Environments By Michael Lück. Retrieved 2009-08-01. 
  4. ^ "Planet Fear". Retrieved 2009-08-04. 
  5. ^ http://www.southwestcoastpath.com/main/sections/index.cfm?fsa=dspSectionDetail&w_id=147
  6. ^ "Polar Sun Spire". SummitPost.Org. Retrieved 2008-07-31. 
  7. ^ "Climbing in Tasermiut". bigwall.dk. Retrieved 2008-09-02. 
  8. ^ "The American Alpine Journal". 1986. Retrieved 2008-09-02. [dead link]
  9. ^ "Geology Fieldnotes". National Park Service. Retrieved 2010-11-28. 
  10. ^ C.Michael Hogan. 2010. Abiotic factor. Encyclopedia of Earth. eds Emily Monosson and C. Cleveland. National Council for Science and the Environment. Washington DC

External links[edit]