Plateau

Plateau
Island in the Sky, Canyonlands National Park

In geology and earth science, a plateau (play /pləˈt/ or /ˈplæt/; plural plateaus or rarely plateaux), also called a high plain or tableland, is an area of highland, usually consisting of relatively flat terrain. A highly eroded plateau is called a dissected plateau. A volcanic plateau is a plateau produced by volcanic activity.

Plateaus can be formed by a number of processes, including, upwelling of volcanic magma, extrusion of lava, and erosion by water and glaciers. Magma rises from the mantle causing the ground to swell upward, in this way large, flat areas of rock are uplifted. Plateaus can also be built up by lava spreading outwards from cracks and weak areas in the crust, an example of such a plateau is the Columbia Plateau in the northwestern United States of America. Plateaus can also be formed due to the erosional processes of glaciers on mountain ranges, in this case the plateaus are left sitting between the mountain ranges. Water can also erode mountains and other landforms down into plateaus.

Plateaus are classified according to their surrounding environment, common categories are: intermontane, piedmont, and continental plateaus.

  • Intermontane plateaus are the highest in the world, these plateaus are bordered by mountains. The Tibetan plateau is one such plateau.
  • Piedmont plateaus are bordered on one side by mountains and on the other by a plain or sea.
  • Continental plateaus are bordered on all sides by the plains or seas, form away from mountains.

Contents

Major plateaus of the world

The largest and highest plateau in the world is the Tibetan Plateau, called the "roof of the world", which is still being formed by the collisions of the Indo-Australian and Eurasian tectonic plates. In all the Tibetan plateau covers an area of some 2.5 million square kilometres which is approximately 5000 m above sea level. The height of this plateau is such that it is enough to reverse the Hadley cell convection cycles and to drive the monsoons of India towards the south.

Bogotá, Colombia is located in a high plateau, over 8,600 ft (2,600 m) high

The second-largest current plateau in the world is the Antarctic Plateau, which covers most of the central part of Antarctica. In that region of Antarctica, there are no mountains that we know of, but rather, there are 3000 meters or more of ice - which very slowly spreads towards its coastline via enormous glaciers. This ice cap is so massive that echo location sound measurements of the thickness of the ice have shown that large parts of the "dry land" surface of Antarctica have been pressed below sea level. Thus, if the icecap were somehow removed, large areas of Antarctica would be flooded by the oceans. On the other hand - more realistically - if that icecap were to gradually melt away, the surface of the land beneath it would gradually rebound away from the center of the Earth, and that land would become land above sea level.

The third-largest plateau in the world is probably the one in South America that lies in the middle of the Andes Mountains. This Andean Plateau covers most of Bolivia, central Ecuador, central Peru, northern Chile and northern Argentina.

Major plateaus of North America

In North America, the largest plateau is the Colorado Plateau covering an area of about 337,000 square kilometres (130,000 sq mi) in Colorado, Utah, Arizona and New Mexico.[1]

The Colorado Plateau in northern Arizona and southern Utah is bisected by the valley of the Colorado River and the Grand Canyon. How this came to be is that over 10 million years ago, a river was already there, though not necessarily on exactly the same course. Then, subterranean geological forces caused the land in that part of North America to gradually rise by about a centimeter per year for millions of years. An unusual balance occurred: the river that would become the Colorado River was able to erode its way down into the crust of the Earth just as fast as the land rose. Now, millions of years later, the North Rim of the Grand Canyon is at an elevation of about 3000 meters (9800 ft) above sea level, and the South Rim of the Grand Canyon is about 2500 meters (8200 ft) above sea level. At its deepest, the Colorado River is about 1600 meters (5200 ft) below the level of the North Rim.

The southern edge of the plateau in northern Arizona is called the Mogollon Rim, where the elevation of the land starts declining rather steeply into central Arizona. This Mogollon Rim is located about 50 kilometers south of these cities and towns: Flagstaff, Holbrook, Sedona, Winslow, and Williams, Arizona. Because of the snowy plateau and the San Francisco Mountains to its north, the Mogollian Rim area is prominient for its many natural springs and artesian wells.

See also

References

  1. ^ Leighty, Dr. Robert D. (2001). "Colorado Plateau Physiographic Province". Contract Report. Defense Advanced Research Projects Agency (DOD) Information Sciences Office. http://www.tec.army.mil/publications/ifsar/lafinal08_01/five/5.1.5_frame.htm. Retrieved 2007-12-25. 

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  • plateau — [ plato ] n. m. • XIIIe « grand plat »; platel « écuelle » fin XIIe; de 1. plat 1 ♦ Support plat servant à poser et à transporter des objets. Plateau de bois, d argent. Plateau de garçon de café, de serveur. Servir le déjeuner, le café sur un… …   Encyclopédie Universelle

  • Plateau — bezeichnet: Hochebene eine erhöhte Aussichtsplattform zwischen Erregung und Orgasmus liegende Phase, siehe Sexueller Reaktionszyklus ein nordamerikanisches Kulturareal der Indianer, siehe Plateau (Kulturareal) ein Departement des Staates Benin,… …   Deutsch Wikipedia

  • Plateau de lœss — Le plateau de Lœss en Chine du Nord (zone hachurée) et la vallée du Huang He (Fleuve Jaune) Le plateau de Lœss ou Huangtu Gaoyuan (黃土高原 ; pinyin : huángtǔ gāoyuán) est un vaste plateau constitué de dépôts sédimentaires éoliens de lœss,… …   Wikipédia en Français

  • Plateau — Saltar a navegación, búsqueda Mapa de Benin, con el Departamento de Plateau resaltando Plateau es uno de los doce departamentos de Benín. Limita con los departamentos de Zou. Ouémé, y Collines. Tiene una superficie de 2.835 km², y una población… …   Wikipedia Español

  • Plateau — Sn Hochebene per. Wortschatz fach. (19. Jh.) Entlehnung. Entlehnt aus frz. plateau, auch flacher Gegenstand , zu frz. plat flach , aus früh rom. * plattus, aus gr. platýs flach, eben, weit, ausgedehnt .    Ebenso nndl. plateau, ne. plateau, nschw …   Etymologisches Wörterbuch der deutschen sprache

  • plateau — Plateau. sub. m. Le fond de bois des grosses balances, dont on se sert pour peser les lourds fardeaux. On appelle aussi du mesme nom de Plateau, Certains petits plats de la Chine de bois vernisé sur lesquels on sert ordinairement le Thé, le Caffé …   Dictionnaire de l'Académie française

  • plateau — ► NOUN (pl. plateaux or plateaus) 1) an area of fairly level high ground. 2) a state or period of little or no change following a period of activity or progress. ► VERB (plateaus, plateaued, plateauing) ▪ reac …   English terms dictionary

  • Plateau — Pla*teau , n.; pl. F. {Plateaux} (F. ?; E. ?), E. {Plateaus}. [F., fr. OF. platel, properly a little plate. See {Plate}.] 1. A flat surface; especially, a broad, level, elevated area of land; a table land. [1913 Webster] 2. An ornamental dish for …   The Collaborative International Dictionary of English

  • Plateau — (fr., spr. Platoh), 1) Platte; 2) so v.w. Hochebene …   Pierer's Universal-Lexikon

  • Plateau [1] — Plateau (franz., spr. tō), Platte; dann besonders soviel wie Hochebene (s. Ebene, S. 336) …   Meyers Großes Konversations-Lexikon

  • Plateau [2] — Plateau (spr. tō), Joseph Anton Ferdinand, Physiker, geb. 14. Okt. 1801 in Brüssel, studierte in Lüttich, war 1835–71 Professor der Experimentalphysik und Astronomie in Gent und starb 15. Sept. 1883 in Gent. Er arbeitete namentlich über Optik und …   Meyers Großes Konversations-Lexikon

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