For other uses, see Canyon (disambiguation).
"Gorge" redirects here. For the figure from Greek mythology, see Gorge (mythology). For the old English meaning, see throat.
|
|
This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (February 2010) |
Fish River Canyon, Namibia
Sianok canyon in Bukittinggi, Indonesia
Kali Gandaki Gorge near Ghassa village, Nepal
Cetina River Canyon, Croatia
Noravank Monastery complex and canyon in Armenia.
Grand Canyon, Arizona, at the confluence of the Colorado and Little Colorado rivers
The Pont d'Arc in the Ardèche gorges in France.
Sapadere Canyon, Antalya, Turkey.
A canyon (occasionally spelled cañon) or gorge is a deep ravine between pairs of escarpments or cliffs and is most often carved from the landscape by the erosive activity of a river over geologic timescales. Rivers have a natural tendency to cut through underlying surfaces so will eventually wear away rock layers to lessen their own pitch slowing their waters; given enough time, their bottoms will gradually reach a baseline elevation—which is the same elevation as the body of water it will eventually drain into. This action, when the river source and mouth are at much different base elevations will form a canyon,[1] particularly through regions where softer rock layers are intermingled with harder layers more resistant to weathering.
Most canyons were formed by a process of long-time erosion from a plateau or table-land level. The cliffs form because harder rock strata that are resistant to erosion and weathering remain exposed on the valley walls. The word canyon is Spanish in origin (cañón, pronounced: [kaˈɲon], meaning big caña, cane in English). The word canyon is generally used in the United States, while the word gorge is more common in Europe and Oceania, though gorge and ravine are also used in some parts of the United States and Canada. The military derived word defile is occasionally used in the United Kingdom.
Canyons are much more common in arid areas than in wet areas because physical weathering has a more localized effect in arid zones. The wind and water from the river combine to erode and cut away less resistant materials such as shales. The freezing and expansion of water also serves to help form canyons. Water seeps into cracks between the rocks and freezes, pushing the rocks apart and eventually causing large chunks to break off the canyon walls, in a process known as frost wedging.[2] Canyon walls are often formed of resistant sandstones or granite. Submarine canyons form underwater, generally at the mouths of rivers.
Sometimes large rivers run through canyons as the result of gradual geological uplift. These are called entrenched rivers, because they are unable to easily alter their course. The Colorado River in the Southwest and the Snake River in the Northwest are two examples of tectonic uplift.
Canyons often form in areas of limestone rock. As Limestone is soluble to a certain extent, cave systems form in the rock. When these collapse a canyon is left, as in the Mendip Hills in Somerset and Yorkshire Dales in Yorkshire, England.
A canyon may also refer to a rift between two mountain peaks such as those in ranges such as the Rocky Mountains, the Alps, the Himalayas or the Andes. Usually a river or stream and erosion carve out such splits between mountains. Examples of mountain type canyons are Provo Canyon in Utah or Yosemite National Park in California's Sierra Nevada. Canyons within mountains or gorges that only have an opening on one side are called box canyons. Slot canyons are very narrow canyons, often with smooth walls.
Contents
- 1 Largest canyons
- 2 Cultural significance
- 3 Lists
- 3.1 List of canyons
- 3.2 List of gorges
- 3.3 List of other features causing gorges or canyons
- 4 Canyons on other planetary bodies
- 5 See also
- 6 Notes
- 7 External links
Largest canyons[edit]
The definition of "largest canyon" is imprecise, as a canyon can be large by its depth, length, or the total area of the canyon system. Also the inaccessibility of the major canyons in the Himalaya contributes to their not being regarded as candidates for the biggest canyon. The definition of "deepest canyon" is similarly imprecise, especially if one includes mountain canyons as well as canyons cut through relatively flat plateaus (which have a somewhat well-defined rim elevation).
The deepest canyon in the world, the Indus Gorge with Nanga Parbat, the world's 9th highest mountain rising to the south.
The Indus Gorge through the Himalaya mountain range in northern Pakistan is the deepest canyon in the world. At the confluence of the Gilgit and Indus rivers along the Karakoram Highway the river flows at an elevation of about 1,000 m (3,300 ft) above sea level. Rising in one continuous sweep above the Indus, the largest such rise on the planet, to the south, just a scant 15 km away, is the summit of the world's 9th highest mountain, Nanga Parbat, 8,126 m (26,660 feet) high. Rising to the north, also visible from the bridge over the Gilgit, is the westernmost of the great Himalayan peaks, Rakaposhi, 7,788 m (25,550 ft) high. That makes the Indus gorge 7,120 m (23,360 ft) deep from river to peak at that point, more than 600 m (2,000 ft) greater than the depth of the Kali Gandaki Gorge and 1,500 m (5,000 ft) deeper than the Yarlung Tsangpo Gorge. These are the three deepest canyons in the world. Only the big mountains of Asia have the prominence for such canyons to be possible. The Andes of South America are high mountains, but not on the same scale as the Himalaya, Karakoram, and Hindu Kush, which all come together at the confluence of the Gilgit and the Indus in Pakistani Kashmir.
The Yarlung Tsangpo Grand Canyon (or Tsangpo Canyon), along the Yarlung Tsangpo River in Tibet, is regarded by some as the deepest canyon in the world at 5,500 m (18,000 ft), and is slightly longer than Grand Canyon.[3] The Kali Gandaki Gorge in midwest Nepal is seen by others to be the deepest canyon, with a 6400 m (21,000 ft) difference between the level of the river and the peaks surrounding it.
View of Grand Canyon from Space Shuttle Challenger.
The Grand Canyon of northern Arizona with an average depth of 1,600 m (one mile) and a volume of 4.17 trillion cubic metres,[4] is one of the world's largest canyons, and was among the 28 finalists of the New7Wonders of Nature worldwide poll. (Some referred to it as one of the 7 natural wonders of the world.[5]) Copper Canyon in Chihuahua, Mexico is deeper and longer than the Grand Canyon.
The largest canyon in Africa is the Fish River Canyon in Namibia.[6]
In August 2013 the discovery of Greenland's Grand Canyon, the longest canyon on the Earth, under the ice sheet, was reported, based on the analysis of date from Operation IceBridge.[7]
Cultural significance[edit]
Some canyons have notable cultural significance. In the southwestern United States, canyons are important archeologically because of the many cliff-dwellings built there, largely by the ancient Pueblo peoples who were their inhabitants. Evidence of early humanoids have been discovered in Africa's Olduvai Gorge.
Lists[edit]
List of canyons[edit]
Fjaðrárgljúfur Canyon, Iceland
Americas
- Grand Canyon, Arizona, United States
- Canyon Sainte-Anne, Quebec, Canada
- Fraser Canyon, British Columbia, Canada
- Horseshoe Canyon, Alberta, Canada
- Ouimet Canyon, Ontario, Canada
- Black Canyon of the Gunnison, Colorado, United States
- Canyon de Chelly, Arizona, United States
- Grand Canyon of the Yellowstone, Wyoming, United States
- Hells Canyon, Idaho and Oregon, United States
- Kings Canyon National Park, California, United States
- Little River Canyon, Alabama, United States
- Logan Canyon, Utah, United States
- Nine Mile Canyon, Utah, United States
- Palo Duro Canyon, Texas, United States
- Waimea Canyon, Hawaii, United States
- Huasteca Canyon, Monterrey, Mexico
- Sumidero Canyon, Chiapas, Mexico
- Copper Canyon, Chihuahua, Mexico
- Somoto Canyon, Somoto, Madriz, Nicaragua
- St. Christopher's Canyon (Cañon de San Cristobal), Barranquitas/Aibonito, Puerto Rico
- Chicamocha Canyon, Santander, Colombia
- Saturban canyon, Santander, Colombia
- Colca Canyon, Arequipa, Peru
- Cotahuasi Canyon, Arequipa, Peru
- Grand Canyon of Torotoro, Torotoro, Potosi Department, Bolivia
- Guartelá Canyon, Paraná, Brazil
- Itaimbezinho, Rio Grande do Sul, Brazil
Africa
- Blyde River Canyon, Mpumalanga, South Africa
- Fish River Canyon, Namibia
Europe
- Fjaðrárgljúfur Canyon, Iceland
- Greenland's Grand Canyon, Greenland
- Nfeye Canyon, Portugal
- Tara River Canyon, Montenegro
- Kanionet e Skraparit, Albania
- Rugova Canyon, Kosovo
- Matka Canyon, Republic of Macedonia
- Verdon Gorge, France
Asia
- Harmanköy Canyon, Bilecik Turkey
- Shnizow Canyon, Uşak, Turkey
- Valla Canyon, Kure, Kastamonu, Turkey
- Charyn Canyon, Kazakhstan
- Indus River Gorge through the Himalaya, Pakistan
- Yarlung Zangbo Grand Canyon, Tibet Autonomous Region, China
Australia
- Kings Canyon (Northern Territory), Australia
List of gorges[edit]
Cataract Gorge, Launceston, Tasmania, Australia
Mossman river and Gorge, Daintree National Park, Australia
- Aragvi River Gorge, Georgia (country)
- Avon Gorge, Bristol, England
- Barron Gorge, Queensland, Australia
- Bog Walk Gorge, Saint Catherine Parish, Jamaica
- Bued Gorge, Benguet, Philippines
- Buller Gorge, Buller, New Zealand
- Cataract Gorge, Launceston, Australia
- Cheddar Gorge, Somerset, England
- Chovar Gorge, Kathmandu, Nepal
- Columbia River Gorge, Oregon/Washington, United States
- Corrieshalloch Gorge, Ullapool, Scotland
- Ebbor Gorge, Somerset, England
- Flume Gorge, New Hampshire, United States
- Galston Gorge, NSW, Australia
- Gorropu, Sardinia, Italy
- Ironbridge Gorge, Shropshire, England
- James River Gorge, Virginia, United States
- Kali Gandaki Gorge, Gandaki, Nepal
- Kloof, KwaZulu-Natal, South Africa (The word Kloof means 'gorge' in Afrikaans)
- Komati Gorge, South Africa
- Lanner Gorge, South Africa
- Lehigh River Gorge, The Poconos, Northeastern, Pennsylvania.
- Letchworth State Park (Genesee River Gorge), New York, United States
- Liechtensteinklamm, Salzburg (state), Austria
- Linville Gorge Wilderness, North Carolina, United States
- Manawatu Gorge, Manawatu, North Island, New Zealand
- Montalban Gorge, Philippines
- New River Gorge, West Virginia, United States
- Niagara Gorge, Canada/United States
- North and South Gorges of North Stradbroke Island, QLD, Australia
- Katherine Gorge of Nitmiluk National Park in Australia
- Olduvai Gorge, Great Rift Valley, Africa
- Pankisi Gorge, Georgia (country)
- Painted Chasm, Chasm Provincial Park, British Columbia, Canada
- Pine Creek Gorge, Pennsylvania, United States
- Quechee Gorge, Vermont, United States
- Red River Gorge, Kentucky, United States
- Richtis Gorge, Crete, Greece
- Rio Grande Gorge, New Mexico, United States
- Ripogenus Gorge, Maine, United States
- Royal Gorge, Colorado, United States
- Samaria Gorge, Crete, Greece
- Siq, Petra, Jordan
- Talari Gorges, Mali
- Tallulah Gorge, Georgia, United States
- Gorges du Tarn, France
- Taroko Gorge of Taroko National Park, Taiwan
- Three Gorges, Chongqing, China
- Tiger Leaping Gorge, Yunnan, China
- Verdon Gorge, Provence, France
- Viamala, Graubünden, Switzerland
- Vikos Gorge, Vikos–Aoös National Park, Greece
List of other features causing gorges or canyons[edit]
- Ardèche River, France
- Bued River, Philippines
- Danube River, Europe
- Iron Gate, Serbia-Romania
- Ruinaulta, cutting Flims Rockslide, Switzerland
- Kings River of the Kings Canyon National Park, California, United States
- South Nahanni River in Canada [1]
- Steall Waterfall of Glen Nevis, Lochaber, Scotland
- Gorges de Hérault, France
- Sierra y Cañones de Guara, Alquezar, Spain
Canyons on other planetary bodies[edit]
- Valles Marineris on Mars, the largest known canyon in the solar system
- Ithaca Chasma on Saturn's moon Tethys
Venus has many craters and canyons on its surface. The troughs on the planet are part of a system of canyons that is more than 6 400 km long.
See also[edit]
- Antecedent drainage stream
- Canyoning
- Dalles
- Draw (terrain)
- Geomorphology
- Gully
- List of landforms
- Ravine
Notes[edit]
- ^ http://www.mountainnature.com/Geology/Canyons.htm
- ^ http://www.bobspixels.com/kaibab.org/geology/gc_geol.htm
- ^ http://www.kepu.net.cn/english/canyon/hiking/hik301.html
- ^ National Park Service
- ^ Truong, Alice (1 July 2011). "Everything About the Grand Canyon". Discovery Communications. Retrieved 5 February 2012.
- ^ Cohen, Callan, Claire Spottiswoode and Jonathan Rossouw (2006) Southern African Birdfinder ISBN 1-86872-725-4, page 210
- ^ "Grand Canyon of Greenland Discovered under Ice"
External links[edit]
Media related to Canyon at Wikimedia Commons
|
River morphology
|
|
| Large-scale features |
- Drainage basin
- Drainage network
- Strahler number (stream order)
- River valley
- River delta
- Estuary
|
|
| Alluvial rivers |
- Meander
- Meander cutoff
- Point bar
- Cut bank
- Riffle
- Stream pool
- Braided river
- Bar (river morphology)
- Anabranch
- River bifurcation
- River channel migration
- Oxbow lake
- Floodplain
- Riparian corridor
- Avulsion (river)
- Mouth bar
- Thalweg
- Channel pattern
|
|
| Bedrock river |
- Canyon
- Knickpoint
- Plunge pool
- Bedrock erosion
|
|
| Bedforms |
- Current ripple
- Dune
- Antidune
- Ait
|
|
| Regional processes |
- Aggradation
- Degradation (geology)
- Base level
- Erosion and tectonics
|
|
| Mechanics |
- Playfair's Law
- Hack's law
- Sediment transport
- Water erosion
- Deposition (geology)
- Exner equation
|
|
|
|
|
