Mountain

This article is about the landform. Mountain was also the name given to the steam locomotive type classified as 4-8-2 in the Whyte notation. Mountain was also the name of a rock band in the late 1960s and early 1970s and The Mountain is the English translation of the name of a faction during the French Revolution.\n----\n, a mountain in New Zealand.]]

A mountain is a landform that extends above the surrounding terrain in a limited area. A mountain is generally much higher and steeper than a hill, but there is considerable overlap, and usage often depends on local custom. Some authorities define a mountain as a peak with a topographic prominence over an arbitrary value, for example the Encylopedia Britannica requires a prominence of 2,000 feet (610 m). A mountain is usually produced by the movement of lithospheric plates, either orogenic movement or epeirogenic movement. The compressional forces, isostatic uplift and intrusion of igneous matter forces surface rock upwards, creating a landform higher than the surrounding features. The height of the feature makes it either a hill or, if higher and steeper, a mountain. The absolute heights of features termed mountains and hills vary greatly according to an area's topography. The major mountains tend to occur in long linear arcs, indicating tectonic plate boundaries and activity. Mountain creation tends to occur in discrete periods, referred to as orogenies (orogeny). Two types of mountain are formed depending on how the rock reacts to the tectonic forces - block mountains or fold mountains. Some isolated mountains were produced by volcanoes, including many apparently small islands that reach a great height above the ocean floor. Block mountains are created when large areas are widely broken up by faults creating large vertical displacements. The uplifted blocks are block mountains or horsts. The intervening dropped blocks are termed graben, these can be small or form extensive rift valley systems. This form of landscape can be seen in East Africa, the Vosges, the Basin and Range province of Western North America and the Rhine valley. Where rock does not fault it folds, either symmetrically or asymmetrically. The upfolds are anticlines and the downfolds are synclines, in asymmetric folding there may also be recumbent and overturned folds. The Jura mountains are an example of folding. Over time, erosion can bring about an inversion of relief, the soft upthrust rock is worn away so the anticlines are actually lower than the tougher rock of the synclines. Heights of mountains are generally given as heights above mean sea level. The highest mountain on Earth is Everest, 8850 m, set in the world's most significant mountain range, the Himalayas. Other definitions of height are possible. The peak that is farthest from the centre of the Earth is Chimborazo in Ecuador. At 6,272 m above sea level it is not even the tallest peak in the Andes, but because the Earth bulges at the equator and Chimborazo is very close to the equator, it is 2,150 m further away from the Earth's centre than Everest. The peak that rises farthest from its base is Mauna Kea on Hawaii, whose peak is over 9,000 m above its base on the floor of the Pacific Ocean. The tallest known mountain in the solar system is Olympus Mons, located on Mars. Some mountains are very difficult to climb, and offer spectacular views. Some people therefore enjoy the sport of mountaineering. Mountains are also the site for the sport of downhill skiing.

See also

\n*List of mountains\n**List of mountains in Nepal\n**List of mountains of the United States\n*Latin names of mountains\n*Mountain range and list of mountain ranges\n*List of mountains on Venus\n*List of Lunar mountains\n*Mountain resort\n*Sky islands Category:Landforms\nCategory:Mountains \n\n\n\n\n\n\n\n\nnah:Tepetl\n\nnds:Barg\n\n\nsimple:Mountain\n\nzh-cn:山