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43-693: The Sierra Ancha is penetrated by few improved roads, and the range is cut by numerous deep, spectacular canyons , particularly on its eastern flank. Little agricultural, commercial, or residential development has taken place, though in the past asbestos mining was carried out at a mine between Asbestos and Zimmerman Points. Cattle ranching is still practiced in the area. Nearby communities include Roosevelt, Tonto Basin , Punkin Center , and Young , Arizona. The Sierra Ancha lies completely within Arizona's Tonto National Forest . Two U.S. Wilderness Areas lie within

86-791: A water gap may occur. In these, erosion from a stream occurs faster than mountain uplift, resulting in a gorge or valley that runs through a mountain range from low-lying country on one side to similar country on the other. Examples of such water gaps include the Manawatū Gorge in New Zealand and the Cumberland Narrows in Maryland . The removal of mass from a region will be isostatically compensated by crustal rebound. If we take into consideration typical crustal and mantle densities, erosion of an average 100 meters of rock across

129-527: A broad, uniform surface will cause the crust to isostatically rebound about 85 meters and will cause only a 15-meter loss of mean surface elevation. An example of isostatic uplift is post-glacial rebound following the melting of ice sheets . The Hudson Bay region of Canada, the Great Lakes of Canada and the United States, and Fennoscandia are currently undergoing gradual rebound as a result of

172-508: A more modest uplift over a large region. Perhaps the most extreme form of orogenic uplift is a continental-continental crustal collision. In this process, two continents are sutured together, and large mountain ranges are produced. The collision of the Indian and Eurasian plates is a good example of the extent to which orogenic uplift can reach. Heavy thrust faulting (of the Indian plate beneath

215-463: A relatively small role, and high peak formation can be more attributed to tectonic processes. Direct measures of the elevation change of the land surface can only be used to estimate erosion or bedrock uplift rates when other controls (such as changes in mean surface elevation, volume of eroded material, timescales and lags of isostatic response, variations in crustal density) are known. In a few cases, tectonic uplift can be seen in coral islands . This

258-687: Is thrust onto continental crust. Basically nappes (thrust sheets) from each plate collide and begin to stack one on top of the other; evidence of this process can be seen in preserved ophiolitic nappes (preserved in the Himalayas ) and in rocks with an inverted metamorphic gradient . The preserved inverted metamorphic gradient indicates that nappes were actually stacked on top of each other so quickly that hot rocks did not have time to equilibrate before being thrust on top of cool rocks. The process of nappe stacking can only continue for so long, as gravity will eventually disallow further vertical growth (there

301-404: Is a deep cleft between escarpments or cliffs resulting from weathering and the erosive activity of a river over geologic time scales . Rivers have a natural tendency to cut through underlying surfaces, eventually wearing away rock layers as sediments are removed downstream. A river bed will gradually reach a baseline elevation, which is the same elevation as the body of water into which

344-579: Is actually 1 km wider than the Grand Canyon, making it the widest canyon in the world. Some canyons have notable cultural significance. Evidence of archaic humans has been discovered in Africa's Olduvai Gorge . In the southwestern United States, canyons are important archeologically because of the many cliff-dwellings built in such areas, largely by the ancient Pueblo people who were their first inhabitants. The following list contains only

387-482: Is an upper limit to vertical mountain growth). Although the raised surfaces of mountain ranges mainly result from crustal thickening, there are other forces at play that are responsible for the tectonic activity. All tectonic processes are driven by gravitational force when density differences are present. A good example of this would be the large-scale circulation of the Earth's mantle . Lateral density variations near

430-541: Is capped with a coarse-grained, brown, Cambrian sandstone analogous to the Tapeats Sandstone of the Grand Canyon . The Tapeats Sandstone lies on an unconformity at 850 m (2,790 ft) in the Grand Canyon, whereas at Aztec Peak it appears at about 2,350 m (7,710 ft), a vertical displacement from which can be inferred about 1,500 m (4,900 ft) of ancient uplift , implying that

473-679: Is evidenced by the presence of various oceanic islands composed entirely of coral , which otherwise appear to be volcanic islands . Examples of such islands are found in the Pacific, notably the three phosphate islets of Nauru , Makatea , and Banaba , as well as Maré and Lifou in New Caledonia ; Fatu Huku in the Marquesas Islands ; and Henderson Island in the Pitcairn Islands . The uplift of these islands

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516-431: Is important, an increase in the mean elevation of a region can only occur in response to tectonic processes of crustal thickening (such as mountain building events), changes in the density distribution of the crust and underlying mantle , and flexural support due to the bending of rigid lithosphere . Tectonic uplift results in denudation (processes that wear away the earth's surface) by raising buried rocks closer to

559-452: Is known to be sensitive to temperature and rainfall. The magnitude of the exhumation a rock has been subjected to may be inferred from geothermobarometry (measuring previous pressure and temperature history of a rock or assemblage). Knowing the pressure and temperature history of a region can yield an estimate of the ambient geothermal gradient and bounds on the exhumation process; however, geobarometric/geothermometric studies do not produce

602-676: Is occasionally used in the United Kingdom . In South Africa, kloof (in Krantzkloof Nature Reserve ) is used along with canyon (as in Blyde River Canyon ) and gorge (in Oribi Gorge ). 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

645-404: Is proportional to the rate of increase of average surface height. The highest rates of working against gravity are required when the thickness of the crust (not the lithosphere) changes. Lithospheric flexure is the process by which the lithosphere bends under the action of forces such as the weight of a growing orogeny or changes in ice thickness related to glaciation. The lithosphere rests on

688-539: 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 Yarlung Tsangpo Grand Canyon (or Tsangpo Canyon), along the Yarlung Tsangpo River in Tibet , is regarded by some as the deepest canyon on Earth at 5,500 metres (18,000 ft). It is slightly longer than the Grand Canyon in

731-598: Is soluble to a certain extent, cave systems form in the rock. When a cave system collapses, a canyon is left, as in the Mendip Hills in Somerset and Yorkshire Dales in Yorkshire , England. A box canyon is a small canyon that is generally shorter and narrower than a river canyon, with steep walls on three sides, allowing access and egress only through the mouth of the canyon. Box canyons were frequently used in

774-450: Is specified. Molnar and England identify three kinds of displacement to which the term "uplift" is applied: This simple equation relates the three kinds of displacement: The term geoid is used above to mean mean sea level and makes a good frame of reference. A given displacement within this frame of reference allows one to quantify the amount of work being done against gravity. Measuring uplift and exhumation can be tricky. Measuring

817-644: Is the Fish River Canyon in Namibia . In August 2013, the discovery of Greenland 's Grand Canyon was reported, based on the analysis of data from Operation IceBridge . It is located under an ice sheet. At 750 kilometres (470 mi) long, it is believed to be the longest canyon in the world. Despite not being quite as deep or long as the Grand Canyon, the Capertee Valley in Australia

860-409: Is the result of the movement of oceanic tectonic plates. Sunken islands or guyots with their coral reefs are the result of crustal subsidence as the oceanic plate carries the islands to deeper or lower oceanic crust areas. The word "uplift" refers to displacement contrary to the direction of the gravity vector, and displacement is only defined when the object being displaced and the frame of reference

903-631: The Alps , the Himalayas or the Andes . Usually, a river or stream carves out such splits between mountains. Examples of mountain-type canyons are Provo Canyon in Utah or Yosemite Valley in California's Sierra Nevada . Canyons within mountains, or gorges that have an opening on only one side, are called box canyons. Slot canyons are very narrow canyons that often have smooth walls. Steep-sided valleys in

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946-461: The United States , place names generally use canyon in the southwest (due to their proximity to Spanish-speaking Mexico ) and gorge in the northeast (which is closer to French Canada ), with the rest of the country graduating between these two according to geography. In Canada , a gorge is usually narrow while a ravine is more open and often wooded. The military-derived word defile

989-487: The asthenosphere , a viscous layer that in geological time scales behaves like a fluid. Thus, when loaded, the lithosphere progressively reaches an isostatic equilibrium. For example, the lithosphere on the oceanward side of an oceanic trench at a subduction zone will curve upwards due to the elastic properties of the Earth's crust. Orogenic uplift is the result of tectonic-plate collisions and results in mountain ranges or

1032-642: The seabed of the continental slope are referred to as submarine canyons . Unlike canyons on land, submarine canyons are thought to be formed by turbidity currents and landslides . The word canyon is Spanish in origin ( cañón , pronounced [kaˈɲon] ), with the same meaning. The word canyon is generally used in North America , while the words gorge and ravine (French in origin) are used in Europe and Oceania , though gorge and ravine are also used in some parts of North America. In

1075-460: The western United States as convenient corrals, with their entrances fenced. The definition of "largest canyon" is imprecise, because a canyon can be large by its depth, its 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"

1118-524: The Eurasian plate) and folding are responsible for the suturing together of the two plates. The collision of the Indian and Eurasian plates produced the Himalayas and is also responsible for crustal thickening north into Siberia . The Pamir Mountains , Tian Shan , Altai , Hindu Kush , and other mountain belts are all examples of mountain ranges formed in response to the collision of the Indian with

1161-755: The Eurasian plate. The Ozark Plateau is a broad uplifted area which resulted from the Permian Ouachita Orogeny to the south in the states of Arkansas , Oklahoma , and Texas . Another related uplift is the Llano Uplift in Texas, a geographical location named after its uplift features. The Colorado Plateau which includes the Grand Canyon is the result of broad tectonic uplift followed by river erosion . When mountains rise slowly, either due to orogenic uplift or other processes (e.g., rebound after glaciation ), an unusual feature known as

1204-527: The Sierra Ancha are Workman Creek and Salome Creek . The classic Sonoran Desert floristic community of saguaro , palo verde , and creosote bush can be found in the southern foothills above Roosevelt Lake (650–1000 m / 2133–3281 ft), while in the range's middle elevations (1200–1800 m / 3937–5906 ft) oak scrub and juniper predominate. Above 6000 feet (1829 m), the Sierra Ancha has extensive stands of ponderosa pine , with Douglas-fir on

1247-768: The Sierra Ancha once stood at least 1500 m higher than the range does today, and that the Paleozoic strata which overlie the Tapeats in the Grand Canyon have been removed in the Sierra Ancha through erosion . Gravels consistent with erosional removal and deposition can be found on top of the Colorado Plateau to the north of the Sierra Ancha. 33°57′27″N 111°11′12″W  /  33.95750°N 111.18667°W  / 33.95750; -111.18667 Canyon A canyon (from Spanish : cañón ; archaic British English spelling: cañon ), gorge or chasm ,

1290-642: The Sierra Ancha — the Salome Wilderness , encompassing Salome Creek and its canyon on the southern edge of the range, and the Sierra Ancha Wilderness , protecting the high peaks and deep canyons of the eastern flank of the range. The range also includes the U.S. Forest Service's Sierra Ancha Experimental Forest, a tract on which research on the characteristics of Southwestern U.S. watersheds has been conducted. The Sierra Ancha includes abundant archaeological remains, especially in

1333-533: The United States, with an average depth of 1,600 metres (5,200 ft) and a volume of 4.17 trillion cubic metres (147 trillion cubic feet), is one of the world's largest canyons. It was among the 28 finalists of the New 7 Wonders of Nature worldwide poll. (Some referred to it as one of the seven natural wonders of the world .) The largest canyon in Europe is Tara River Canyon . The largest canyon in Africa

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1376-627: The United States. Others consider the Kali Gandaki Gorge in midwest Nepal to be the deepest canyon, with a 6,400-metre (21,000 ft) difference between the level of the river and the peaks surrounding it. Vying for the deepest canyon in the Americas is the Cotahuasi Canyon and Colca Canyon , in southern Peru. Both have been measured at over 3,500 metres (11,500 ft) deep. The Grand Canyon of northern Arizona in

1419-746: The canyon walls, in a process known as frost wedging. Canyon walls are often formed of resistant sandstones or granite . 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. In the United States, 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

1462-549: The form of cliff dwellings in the rugged canyons opening eastward toward Cherry Creek. The identity of the American Indian builders of these structures remains uncertain, but the sites show characteristics of both the Salado and Mogollon cultures. Tree-ring dating of roof beams from the sites suggests that construction began in about 1280 AD, and that the structures were abandoned by 1350 AD. Prominent streams within

1505-714: The highest, coolest slopes. The Sierra Ancha holds a disjunctive population of coastal woodfern, Dryopteris arguta , which is typically found closer to the Pacific Ocean, owing to the relatively humid climate of the upper elevations of the range. The Sierra Ancha features significant exposures of the Apache Group , a complex consisting of Proterozoic conglomerate , shale , dolomitic limestone , and quartzite , with large-scale intrusions of diabase . The purplish Dripping Spring Quartzite and white-pinkish Troy Quartzite are much more resistant to weathering than

1548-451: The melting of ice sheets 10,000 years ago. Crustal thickening, which for example is currently occurring in the Himalayas due to the continental collision between the Indian and the Eurasian plates, can also lead to surface uplift; but due to the isostatic sinking of thickened crust, the magnitude of surface uplift will only be about one-sixth of the amount of crustal thickening. Therefore, in most convergent boundaries , isostatic uplift plays

1591-412: The most notable canyons of the world, grouped by region. 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. [REDACTED] Environment portal Tectonic uplift Tectonic uplift is the geologic uplift of Earth's surface that is attributed to plate tectonics . While isostatic response

1634-468: The river drains. The processes of weathering and erosion will form canyons when the river's headwaters and estuary are at significantly different elevations, particularly through regions where softer rock layers are intermingled with harder layers more resistant to weathering. A canyon may also refer to a rift between two mountain peaks, such as those in ranges including the Rocky Mountains ,

1677-417: The surface (such as the creation, cooling, and subduction of oceanic plates ) also drive plate motion. The dynamics of mountain ranges are governed by differences in the gravitational energy of entire columns of the lithosphere (see isostasy ). If a change in surface height represents an isostatically compensated change in crustal thickness, the rate of change of potential energy per unit surface area

1720-436: The surface. This process can redistribute large loads from an elevated region to a topographically lower area as well – thus promoting an isostatic response in the region of denudation (which can cause local bedrock uplift). The timing, magnitude, and rate of denudation can be estimated by geologists using pressure-temperature studies. Crustal thickening has an upward component of motion and often occurs when continental crust

1763-650: The surrounding strata and form the Sierra Ancha's spectacular cliffs. In lower Parker Canyon, on the range's south face, the Dripping Springs Quartzite forms precipices with a 200 m (700 ft) vertical drop. The light-colored cliffs topping upper Parker Canyon have been formed from the Troy Quartzite. The basement (lowest) rock throughout the range consists of the Proterozoic Ruin Granite . The top of Aztec Peak

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1806-690: The uplift of a point requires measuring its elevation change – usually geoscientists are not trying to determine the uplift of a singular point but rather the uplift over a specified area. Accordingly, the change in elevation of all points on the surface of that area must be measured, and the rate of erosion must be zero or minimal. Also, sequences of rocks deposited during that uplift must be preserved. Needless to say, in mountain ranges where elevations are far above sea level these criteria are not easily met. Paleoclimatic restorations though can be valuable; these studies involve inferring changes in climate in an area of interest from changes with time of flora/fauna that

1849-456: The valley walls. 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

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