Amountain range orhill range is a series ofmountains orhills arranged in a line and connected by high ground. Amountain system ormountain belt is a group of mountain ranges with similarity in form, structure, and alignment that have arisen from the same cause, usually anorogeny.[1] Mountain ranges are formed by a variety of geological processes, but most of the significant ones on Earth are the result ofplate tectonics.[2] Mountain ranges are also found on many planetary mass objects in theSolar System and are likely a feature of mostterrestrial planets.
TheAndes, the longest mountain range on the surface of the Earth, have a dramatic impact on the climate of South America
The position of mountain ranges influences climate, such as rain or snow.[8] When air masses move up and over mountains, the air cools, producingorographic precipitation (rain or snow). As the air descends on the leeward side, it warms again (following theadiabatic lapse rate) and is drier, having been stripped of much of its moisture. Often, arain shadow will affect the leeward side of a range.[9] As a consequence, large mountain ranges, such as the Andes, compartmentalize continents into distinctclimate regions.
Mountain ranges are constantly subjected toerosional forces which work to tear them down.[10] Thebasins adjacent to an eroding mountain range are then filled with sediments that are buried and turned intosedimentary rock. Erosion is at work while the mountains are being uplifted until the mountains are reduced to low hills and plains.
The earlyCenozoic uplift of theRocky Mountains of Colorado provides an example. As the uplift was occurring some 10,000 feet (3,000 m) of mostlyMesozoic sedimentarystrata were removed by erosion over the core of the mountain range and spread as sand and clays across theGreat Plains to the east.[11] This mass of rock was removed as the range was actively undergoing uplift. The removal of such a mass from the core of the range most likely caused further uplift as the region adjustedisostatically in response to the removed weight.
Rivers are traditionally believed to be the principal cause of mountain range erosion, by cutting into bedrock and transporting sediment. Computer simulation has shown that as mountain belts change from tectonically active to inactive, the rate of erosion drops because there are fewer abrasive particles in the water and fewer landslides.[12]
Mountains on other planets andnatural satellites of the Solar System, including theMoon, are often isolated and formed mainly by processes such as impacts, though there are examples of mountain ranges (or "Montes") somewhat similar to those on Earth.Saturn's moonTitan[13] andPluto,[14] in particular, exhibit large mountain ranges in chains composed mainly of ices rather than rock. Examples include theMithrim Montes andDoom Mons on Titan, andTenzing Montes andHillary Montes on Pluto. Some terrestrial planets other than Earth also exhibit rocky mountain ranges, such asMaxwell Montes onVenus taller than any on Earth[15] andTartarus Montes onMars.[16] Jupiter's moonIo has mountain ranges formed from tectonic processes including theBoösaule, Dorian, Hi'iaka andEuboea Montes.[17]
