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74-518: The Nafud is an erg , a desert region located in north-central Saudi Arabia . It is noted for its sudden violent winds, which account for the large crescent-shaped dunes . The sand in the Nafud is a brick-reddish color. Rain comes once or twice per year. In some lowland areas, namely those near the Hejaz Mountains, there are oases where dates, vegetables, barley, and fruits are grown. The Nafud

148-540: A geological feature that can be found on planets where an atmosphere capable of significant wind erosion acts on the surface for a significant period of time, creating sand and allowing it to accumulate. Today at least three bodies in the Solar System , apart from Earth, are known to feature ergs on their surface: Venus, Mars and Titan. At least two ergs have been recognized by the Magellan probe on Venus :

222-555: A higher potential for larger, high-magnitude earthquakes in the future. The mountain range is also a source of shallow intraplate earthquakes within the South American Plate. The largest such earthquake (as of 2024) struck Peru in 1947 and measured M s   7.5. In the Peruvian Andes, these earthquakes display normal ( 1946 ), strike-slip (1976), and reverse ( 1969 , 1983) mechanisms. The Amazonian Craton

296-566: A joint ice stream network. The Andes' dendritic glacier arms, components of valley glaciers, were up to 112.5 km (69.9 mi) long and over 1,250 m (4,101 ft) thick, and spanned a vertical distance of 5,150 m (16,896 ft). The climatic glacier snowline (ELA) was lowered from 4,600 m (15,092 ft) to 3,200 m (10,499 ft) at glacial times. The Andean region cuts across several natural and floristic regions, due to its extension, from Caribbean Venezuela to cold, windy, and wet Cape Horn passing through

370-594: A north–south axis of cultural influences. A long series of cultural development culminated in the expansion of the Inca civilization and Inca Empire in the central Andes during the 15th century. The Incas formed this civilization through imperialistic militarism as well as careful and meticulous governmental management. The government sponsored the construction of aqueducts and roads in addition to pre-existing installations. Some of these constructions still exist today. Devastated by European diseases and by civil war ,

444-711: A series of bends or oroclines . The Bolivian Orocline is a seaward-concave bending in the coast of South America and the Andes Mountains at about 18° S. At this point, the orientation of the Andes turns from northwest in Peru to south in Chile and Argentina . The Andean segments north and south of the Orocline have been rotated 15° counter-clockwise to 20° clockwise respectively. The Bolivian Orocline area overlaps with

518-634: A typical location for calc-alkalic and subduction volcanism, the Andean Volcanic Belt has a large range of volcano-tectonic settings, such as rift systems, extensional zones, transpressional faults , subduction of mid-ocean ridges , and seamount chains apart from a large range of crustal thicknesses and magma ascent paths, and different amount of crustal assimilations. The Andes Mountains host large ore and salt deposits, and some of their eastern fold and thrust belts act as traps for commercially exploitable amounts of hydrocarbons . In

592-536: A whole glacier in the ablation area or in the accumulation area . In the high Andes of Central Chile and Mendoza Province , rock glaciers are larger and more common than glaciers; this is due to the high exposure to solar radiation . In these regions, glaciers occur typically at higher altitudes than rock glaciers. The lowest active rock glaciers occur at 900 m a.s.l. in Aconcagua . Though precipitation increases with height, there are semiarid conditions in

666-780: A zone of volcanic activity that encompasses the Pacific rim of the Americas as well as the Asia-Pacific region. The Andes are the result of tectonic plate processes extending during the Mesozoic and Tertiary eras, caused by the subduction of oceanic crust beneath the South American Plate as the Nazca Plate and South American Plate converge. These processes were accelerated by the effects of climate. As

740-561: Is a result of the subduction of the Nazca Plate and Antarctic Plate underneath the South American Plate. The belt is subdivided into four main volcanic zones that are separated from each other by volcanic gaps. The volcanoes of the belt are diverse in terms of activity style, products, and morphology. While some differences can be explained by which volcanic zone a volcano belongs to, there are significant differences inside volcanic zones and even between neighboring volcanoes. Despite being

814-551: Is actively underthrusted beneath the sub-Andes region of Peru, producing thrust faults. In Colombia, Ecuador, and Peru, thrust faulting occurs along the sub-Andes due in response to compression brought on by subduction, while in the high Andes, normal faulting occurs in response to gravitational forces. In the extreme south, a major transform fault separates Tierra del Fuego from the small Scotia Plate . The Andes range has many active volcanoes distributed in four volcanic zones separated by areas of inactivity. The Andean volcanism

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888-619: Is connected to the Rub' al Khali by the Dahna , a corridor of gravel plains and sand dunes, 800 mi (1,287 km) long and 15 to 50 miles (24.1 to 80.5 km) wide. During the Arab Revolt in 1917, forces led by Auda ibu Tayi attacked the Turkish-held coastal town of Aqaba on its poorly defended eastern flank. The approach was via a long and wide desert route, passing close to

962-627: Is halted or slowed by topographic barriers to windflow or by convergence of windflow. Entire ergs and dune fields tend to migrate downwind as far as hundreds of kilometers from their sources of sand. Such accumulation requires long periods of time. At least one million years is required to build ergs with very large dunes, such as those on the Arabian Peninsula , in North Africa, and in central Asia. Sand seas that have accumulated in subsiding structural and topographic basins, such as

1036-471: Is natural, or the result of clearing which began during the Incan period. Regardless, in modern times , the clearance has accelerated, and the trees are now considered highly endangered , with some believing that as little as 10% of the original woodland remains. The Andes are rich in fauna: With almost 1,000 species, of which roughly 2/3 are endemic to the region, the Andes are the most important region in

1110-1647: Is the largest city of all Andean countries. It is the seat of the Andean Community of Nations . La Paz , Bolivia 's seat of government, is the highest capital city in the world, at an elevation of approximately 3,650 m (11,975 ft). Parts of the La Paz conurbation, including the city of El Alto , extend up to 4,200 m (13,780 ft). Other cities in or near the Andes include Bariloche , Catamarca , Jujuy , Mendoza , Salta , San Juan , Tucumán , and Ushuaia in Argentina; Calama and Rancagua in Chile; Cochabamba , Oruro , Potosí , Sucre , Tarija , and Yacuiba in Bolivia; Arequipa , Cajamarca , Cusco , Huancayo , Huánuco , Huaraz , Juliaca , and Puno in Peru; Ambato , Cuenca , Ibarra , Latacunga , Loja , Riobamba , and Tulcán in Ecuador; Armenia , Cúcuta , Bucaramanga , Duitama , Ibagué , Ipiales , Manizales , Palmira , Pasto , Pereira , Popayán , Sogamoso , Tunja , and Villavicencio in Colombia; and Barquisimeto , La Grita , Mérida , San Cristóbal , Tovar, Trujillo , and Valera in Venezuela. The cities of Caracas , Valencia , and Maracay are in

1184-404: The 2010 Maule earthquake (M8.8), the 2015 Illapel earthquake (M8.2), and the 1960 Valdivia earthquake (M9.5), which as of 2024 was the strongest ever recorded on seismometers. The amount, magnitude, and type of seismic activity varies greatly along the subduction zone. These differences are due to a wide range of factors, including friction between the plates, angle of subduction, buoyancy of

1258-682: The Americas and Antarctica . The etymology of the word Andes has been debated. The majority consensus is that it derives from the Quechua word anti "east" as in Antisuyu (Quechua for "east region"), one of the four regions of the Inca Empire . The term cordillera comes from the Spanish word cordel "rope" and is used as a descriptive name for several contiguous sections of

1332-456: The Andean cock-of-the-rock , while mixed-species flocks dominated by tanagers and furnariids are commonly seen—in contrast to several vocal but typically- cryptic species of wrens , tapaculos , and antpittas . A number of species such as the royal cinclodes and white-browed tit-spinetail are associated with Polylepis , and consequently also threatened . The Andes Mountains form

1406-563: The Arabic word ʿirq ( عرق ), meaning "dune field". Strictly speaking, an erg is defined as a desert area that contains more than 125 km (48 sq mi) of aeolian or wind-blown sand and where sand covers more than 20% of the surface. Smaller areas are known as "dune fields". The largest hot desert in the world, the Sahara , covers 9 million square kilometres (3.5 × 10 ^  sq mi) and contains several ergs, such as

1480-592: The Caribbean Sea off the coast of Venezuela, were formerly thought to represent the submerged peaks of the extreme northern edge of the Andes range, but ongoing geological studies indicate that such a simplification does not do justice to the complex tectonic boundary between the South American and Caribbean plates . The Andes are an orogenic belt of mountains along the Pacific Ring of Fire ,

1554-535: The Cenozoic . Tectonic forces above the subduction zone along the entire west coast of South America where the Nazca Plate and a part of the Antarctic Plate are sliding beneath the South American Plate continue to produce an ongoing orogenic event resulting in minor to major earthquakes and volcanic eruptions to this day. Many high-magnitude earthquakes have been recorded in the region, such as

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1628-1002: The Chech Erg and the Issaouane Erg in Algeria . Approximately 85% of all the Earth's mobile sand is found in ergs that are greater than 32,000 km (12,355 sq mi), the largest being the Rub' al Khali , the Empty Quarter of the Arabian Peninsula . Ergs are also found on other celestial bodies , such as Venus , Mars , and Saturn 's moon Titan . Sand seas and dune fields generally occur in regions downwind of copious sources of dry, loose sand, such as dry riverbeds and deltas , floodplains , glacial outwash plains , dry lakes , and beaches . Ergs are concentrated in two broad belts between 20° to 40°N and 20° to 40°S latitudes, which include regions crossed by

1702-734: The Murzuk Sand Sea of Libya , may attain great thicknesses (more than 1000 m ) but others, such as the ergs of linear dunes in the Simpson Desert and Great Sandy Desert of Australia, may be no thicker than the individual dunes superposed on the alluvial plain . Within sand seas in a given area, the dunes tend to be of a single type. For example, there are ergs or fields of linear dunes, of crescentic dunes, of star dunes, and of parabolic dunes, and these dune arrays tend to have consistent orientations and sizes. By nature, ergs are very active. Smaller dunes form and migrate along

1776-642: The Tropical Andes , the Dry Andes , and the Wet Andes . The Andes are the highest mountain range which is outside of Asia . The range's highest peak, Argentina's Aconcagua , rises to an elevation of about 6,961 m (22,838 ft) above sea level. The peak of Chimborazo in the Ecuadorian Andes is farther from the Earth's center than any other location on the Earth's surface, due to

1850-582: The Venezuelan Coastal Range , which is a debatable extension of the Andes at the northern extremity of South America. Cities and large towns are connected with asphalt -paved roads, while smaller towns are often connected by dirt roads, which may require a four-wheel-drive vehicle. The rough terrain has historically put the costs of building highways and railroads that cross the Andes out of reach of most neighboring countries, even with modern civil engineering practices. For example,

1924-674: The War of the Pacific between Chile and the allied Bolivia and Peru, in a diplomatic deal to keep Peru out of the war. The Chilean Army and Chilean Navy defeated the combined forces of Bolivia and Peru, and Chile took over Bolivia's only province on the Pacific Coast, some land from Peru that was returned to Peru decades later. Bolivia has been completely landlocked ever since. It mostly uses seaports in eastern Argentina and Uruguay for international trade because its diplomatic relations with Chile have been suspended since 1978. Because of

1998-602: The equatorial bulge resulting from the Earth's rotation . The world's highest volcanoes are in the Andes, including Ojos del Salado on the Chile-Argentina border, which rises to 6,893 m (22,615 ft). The Andes are also part of the American Cordillera , a chain of mountain ranges ( cordillera ) that consists of an almost continuous sequence of mountain ranges that form the western "backbone" of

2072-483: The rodent order, inhabit the Andes' alpine regions. The Andean condor , the largest bird of its kind in the Western Hemisphere , occurs throughout much of the Andes but generally in very low densities. Other animals found in the relatively open habitats of the high Andes include the huemul , cougar , foxes in the genus Pseudalopex , and, for birds, certain species of tinamous (notably members of

2146-703: The 1,000-kilometer-wide (620 mi) Drake Passage lie the mountains of the Antarctic Peninsula south of the Scotia Plate , which appear to be a continuation of the Andes chain. The far east regions of the Andes experience a series of changes resulting from the Andean orogeny. Parts of the Sunsás Orogen in Amazonian craton disappeared from the surface of the earth, being overridden by

2220-577: The Aglaonice dune field, which covers approximately 1,290 km (500 sq mi), and the Meshkenet dune field (~17,120 km or 6,600 sq mi). These seem to be mostly transverse dune fields (with dune crests perpendicular to prevailing winds). Mars shows very large ergs, especially next to the polar caps, where dunes can reach a considerable size. Ergs on Mars can exhibit strange shapes and patterns, due to complex interaction with

2294-469: The Andean peoples are those of the Quechua and Aymara language families. Woodbine Parish and Joseph Barclay Pentland surveyed a large part of the Bolivian Andes from 1826 to 1827. In modern times, the largest cities in the Andes are Bogotá , with a metropolitan population of over ten million, and Santiago , Medellín , Cali , and Quito . Lima is a coastal city adjacent to the Andes and

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2368-405: The Andes are tobacco and potatoes . The high-altitude Polylepis forests and woodlands are found in the Andean areas of Colombia , Ecuador , Peru , Bolivia , and Chile . These trees, by locals referred to as Queñua, Yagual, and other names, can be found at altitudes of 4,500 m (14,760 ft) above sea level. It remains unclear if the patchy distribution of these forests and woodlands

2442-510: The Andes are split into several ranges, separated by intermediate depressions . The Andes are the location of several high plateaus —some of which host major cities such as Quito , Bogotá , Cali , Arequipa , Medellín , Bucaramanga , Sucre , Mérida , El Alto , and La Paz . The Altiplano Plateau is the world's second highest after the Tibetan Plateau . These ranges are in turn grouped into three major divisions based on climate:

2516-521: The Andes end at the Pacific Ocean , although the Peru-Chile trench can be considered their ultimate western limit. From a geographical approach, the Andes are considered to have their western boundaries marked by the appearance of coastal lowlands and less-rugged topography. The Andes also contain large quantities of iron ore located in many mountains within the range. The Andean orogen has

2590-462: The Andes such as the Incas have practiced irrigation techniques for over 6,000 years. Because of the mountain slopes, terracing has been a common practice. Terracing, however, was only extensively employed after Incan imperial expansions to fuel their expanding realm. The potato holds a very important role as an internally-consumed staple crop. Maize was also an important crop for these people, and

2664-526: The Andes varies greatly depending on latitude, altitude, and proximity to the sea. Temperature, atmospheric pressure, and humidity decrease in higher elevations. The southern section is rainy and cool, while the central section is dry. The northern Andes are typically rainy and warm, with an average temperature of 18 °C (64 °F) in Colombia . The climate is known to change drastically in rather short distances. Rainforests exist just kilometers away from

2738-542: The Andes, as well as the entire Andean range, and the combined mountain chain along the western part of the North and South American continents. The Andes can be divided into three sections: At the northern end of the Andes, the separate Sierra Nevada de Santa Marta range is often, but not always, treated as part of the Northern Andes. The Leeward Antilles islands Aruba , Bonaire , and Curaçao , which lie in

2812-524: The Andes. The Sierras de Córdoba , where the effects of the ancient Pampean orogeny can be observed, owe their modern uplift and relief to the Andean orogeny in the Tertiary . Further south in southern Patagonia , the onset of the Andean orogeny caused the Magallanes Basin to evolve from being an extensional back-arc basin in the Mesozoic to being a compressional foreland basin in

2886-491: The Incas were defeated in 1532 by an alliance composed of tens of thousands of allies from nations they had subjugated (e.g. Huancas , Chachapoyas , Cañaris ) and a small army of 180 Spaniards led by Francisco Pizarro . One of the few Inca sites the Spanish never found in their conquest was Machu Picchu , which lay hidden on a peak on the eastern edge of the Andes where they descend to the Amazon. The main surviving languages of

2960-478: The Patagonian Orocline. The western rim of the South American Plate has been the place of several pre-Andean orogenies since at least the late Proterozoic and early Paleozoic , when several terranes and microcontinents collided and amalgamated with the ancient cratons of eastern South America, by then the South American part of Gondwana . The formation of the modern Andes began with

3034-592: The area of the maximum width of the Altiplano Plateau , and according to Isacks (1988) the Orocline is related to crustal shortening . The specific point at 18° S where the coastline bends is known as the Arica Elbow. Further south lies the Maipo Orocline, a more subtle orocline between 30° S and 38°S with a seaward-concave break in the trend at 33° S. Near the southern tip of the Andes lies

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3108-399: The dry climate that reduced the disturbing actions of meteoric water . The dry climate in the central western Andes has also led to the creation of extensive saltpeter deposits which were extensively mined until the invention of synthetic nitrates . Yet another result of the dry climate are the salars of Atacama and Uyuni , the former being the largest source of lithium and the latter

3182-532: The dry season (winter) possible and allows the cultivation of frost-resistant vegetable crops like onion and carrot . The Andes rose to fame for their mineral wealth during the Spanish conquest of South America . Although Andean Amerindian peoples crafted ceremonial jewelry of gold and other metals, the mineralizations of the Andes were first mined on a large scale after the Spanish arrival. Potosí in present-day Bolivia and Cerro de Pasco in Peru were among

3256-528: The dry, subsiding air of the trade winds . Active ergs are limited to regions that receive, on average, no more than 150 mm of annual precipitation. The largest are in northern and southern Africa , central and western Asia , and Central Australia . In South America , ergs are limited by the Andes Mountains , but they do contain extremely large dunes in coastal Peru and northwestern Argentina . They are also found in several parts of

3330-466: The earliest evidence of modern humans outside Africa and the Levant . This article about the geography of Saudi Arabia is a stub . You can help Misplaced Pages by expanding it . Erg (landform) An erg (also sand sea or dune sea , or sand sheet if it lacks dunes ) is a broad, flat area of desert covered with wind -swept sand with little or no vegetative cover. The word is derived from

3404-471: The edge of the Nafud. Colonel T. E. Lawrence asked Auda ibu Tayi to allow their group to stray from their course into the Nafud. Auda refused because it was unnecessary. Their harsh transit did not include entering the Nafud, as is depicted in the film Lawrence of Arabia . The discovery of an 85,000-year-old fossilised human finger in An Nafud in 2016 by Dr Mathieu Duval of Griffith University provided

3478-501: The establishment of the century-long Inca Empire . This all changed in the 16th century, when the Spanish conquistadors colonized the mountains in advance of the mining economy. In the tide of anti-imperialist nationalism, the Andes became the scene of a series of independence wars in the 19th century, when rebel forces swept through the region to overthrow Spanish colonial rule. Since then, many former Spanish territories have become five independent Andean states. The climate in

3552-705: The events of the Triassic , when Pangaea began the breakup that resulted in developing several rifts . The development continued through the Jurassic Period. It was during the Cretaceous Period that the Andes began to take their present form, by the uplifting , faulting , and folding of sedimentary and metamorphic rocks of the ancient cratons to the east. The rise of the Andes has not been constant, as different regions have had different degrees of tectonic stress, uplift, and erosion . Across

3626-423: The extreme in the slopes near the virtually-lifeless Atacama Desert. About 30,000 species of vascular plants live in the Andes, with roughly half being endemic to the region, surpassing the diversity of any other hotspot . The small tree Cinchona pubescens , a source of quinine which is used to treat malaria , is found widely in the Andes as far south as Bolivia. Other important crops that originated from

3700-462: The flanks of the larger dunes and sand ridges. Occasional precipitation fills basins formed by the dunes; as the water evaporates, salt deposits are left behind. Individual dunes in ergs typically have widths, lengths, or both dimensions greater than 500 m (1,600 ft). Both the regional extent of their sand cover and the complexity and great size of their dunes distinguish ergs from dune fields. The depth of sand in ergs varies widely around

3774-464: The forelands of the Atacama Desert , some of the largest porphyry copper mineralizations occur, making Chile and Peru the first- and second-largest exporters of copper in the world. Porphyry copper in the western slopes of the Andes has been generated by hydrothermal fluids (mostly water) during the cooling of plutons or volcanic systems. The porphyry mineralization further benefited from

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3848-555: The genus Nothoprocta ), Andean goose , giant coot , flamingos (mainly associated with hypersaline lakes), lesser rhea , Andean flicker , diademed sandpiper-plover , miners , sierra-finches and diuca-finches . Lake Titicaca hosts several endemics, among them the highly endangered Titicaca flightless grebe and Titicaca water frog . A few species of hummingbirds , notably some hillstars , can be seen at altitudes above 4,000 m (13,100 ft), but far higher diversities can be found at lower altitudes, especially in

3922-512: The glaciers were over ten times longer. On the east side of this section of the Mendozina Andes, they flowed down to 2,060 m (6,759 ft) and on the west side to about 1,220 m (4,003 ft) above sea level. The massifs of Aconcagua (6,961 m (22,838 ft)), Tupungato (6,550 m (21,490 ft)), and Nevado Juncal (6,110 m (20,046 ft)) are tens of kilometres away from each other and were connected by

3996-556: The humid Andean forests (" cloud forests ") growing on slopes in Colombia, Ecuador, Peru, Bolivia, and far northwestern Argentina. These forest-types, which includes the Yungas and parts of the Chocó, are very rich in flora and fauna, although few large mammals exist, exceptions being the threatened mountain tapir , spectacled bear , and yellow-tailed woolly monkey . Birds of humid Andean forests include mountain toucans , quetzals , and

4070-467: The hyperarid Atacama Desert . Rainforests and tropical dry forests used to encircle much of the northern Andes but are now greatly diminished , especially in the Chocó and inter-Andean valleys of Colombia. Opposite the humid Andean slopes are the relatively dry Andean slopes in most of western Peru, Chile, and Argentina. Along with several Interandean Valles , they are typically dominated by deciduous woodland, shrub and xeric vegetation, reaching

4144-412: The ice bedrock, possibly in the form of flash floods. Alternatively, the sand could also have come from organic solids produced by photochemical reactions in Titan's atmosphere. Andes The Andes ( / ˈ æ n d iː z / AN -deez ), Andes Mountains or Andean Mountain Range ( Spanish : Cordillera de los Andes ; Quechua : Anti ) are the longest continental mountain range in

4218-439: The larger glaciers descend to sea level. The Andes of Chile and Argentina can be divided into two climatic and glaciological zones: the Dry Andes and the Wet Andes . Since the Dry Andes extend from the latitudes of the Atacama Desert to the area of the Maule River , precipitation is more sporadic, and there are strong temperature oscillations. The line of equilibrium may shift drastically over short periods of time, leaving

4292-669: The largest dune field coverage in the Solar System identified to date. The sand dunes are believed to be formed by wind generated as a result of tidal forces from Saturn on Titan's atmosphere. The images are evidence that these dunes were built from winds that blow in one direction before switching to another and then back to the first direction and so on, causing the sand dunes to build up in long parallel lines. These tidal winds combined with Titan's west-to-east zonal winds create dunes aligned west-to-east nearly everywhere except close to mountains, which alter wind direction. The sand on Titan might have formed when liquid methane rained and eroded

4366-432: The main crossover of the Andes between Argentina and Chile is still accomplished through the Paso Internacional Los Libertadores . Only recently have the ends of some highways that came rather close to one another from the east and the west been connected. Much of the transportation of passengers is done via aircraft. However, there is one railroad that connects Chile with Peru via the Andes, and there are others that make

4440-445: The nearly-7,000-metre (22,966 ft) highest mountains of the Andes. This dry steppe climate is considered to be typical of the subtropical position at 32–34° S. The valley bottoms have no woods, just dwarf scrub. The largest glaciers, for example the Plomo Glacier and the Horcones Glaciers, do not even reach 10 km (6.2 mi) in length and have only insignificant ice thickness. At glacial times, however, c. 20,000 years ago,

4514-639: The northeast coast of Brazil . The only active erg in North America is in the Gran Desierto de Altar that extends from the Sonoran Desert in the northwestern Mexican state of Sonora to the Yuma Desert of Arizona and the Algodones Dunes of southeastern California . An erg that has been fixed by vegetation forms the Nebraska Sandhills . Almost all major ergs are located downwind from river beds in areas that are too dry to support extensive vegetative cover and are thus subject to long-continued wind erosion. Sand from these abundant sources migrates downwind and builds up into very large dunes where its movement

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4588-402: The rainy season (summer), part of the rangeland is used for cropping (mainly potatoes, barley, broad beans, and wheat). Irrigation is helpful in advancing the sowing data of the summer crops, which guarantees an early yield in periods of food shortage. Also, by early sowing, maize can be cultivated higher up in the mountains (up to 3,800 m (12,500 ft)). In addition, it makes cropping in

4662-460: The same connection via southern Bolivia. There are multiple highways in Bolivia that cross the Andes. Some of these were built during a period of war between Bolivia and Paraguay , in order to transport Bolivian troops and their supplies to the war front in the lowlands of southeastern Bolivia and western Paraguay. For decades, Chile claimed ownership of land on the eastern side of the Andes. However, these claims were given up in about 1870 during

4736-669: The snow-covered peak of Cotopaxi . The mountains have a large effect on the temperatures of nearby areas. The snow line depends on the location. It is between 4,500 and 4,800 m (14,764 and 15,748 ft) in the tropical Ecuadorian, Colombian, Venezuelan, and northern Peruvian Andes, rising to 4,800–5,200 m (15,748–17,060 ft) in the drier mountains of southern Peru and northern Chile south to about 30°S before descending to 4,500 m (14,760 ft) on Aconcagua at 32°S , 2,000 m (6,600 ft) at 40°S , 500 m (1,640 ft) at 50°S , and only 300 m (980 ft) in Tierra del Fuego at 55°S ; from 50°S, several of

4810-526: The subducting plate, rate of subduction, and hydration value of the mantle material. The highest rate of seismic activity is observed in the central portion of the boundary, between 33°S and 35°S. In this area, the angle of subduction is very low, meaning the subducting plate is nearly horizontal. Studies of mantle hydration across the subduction zone have shown a correlation between increased material hydration and lower-magnitude, more-frequent seismic activity. Zones exhibiting dehydration instead are thought to have

4884-406: The subduction of the Nazca Plate and the Antarctic Plate . To the east, the Andes range is bounded by several sedimentary basins , such as the Orinoco Basin , the Amazon Basin , the Madre de Dios Basin, and the Gran Chaco , that separate the Andes from the ancient cratons in eastern South America. In the south, the Andes share a long boundary with the former Patagonia Terrane . To the west,

4958-452: The tortuous terrain in places, villages and towns in the mountains—to which travel via motorized vehicles is of little use—are still located in the high Andes of Chile, Bolivia, Peru, and Ecuador . Locally, the relatives of the camel , the llama , and the alpaca continue to carry out important uses as pack animals, but this use has generally diminished in modern times. Donkeys , mules , and horses are also useful. The ancient peoples of

5032-431: The underlying surface and wind direction. Radar images captured by the Cassini spacecraft as it flew by Titan in October 2005 show sand dunes at Titan's equator much like those in deserts of Earth. One erg was observed to be more than 930 miles (1,500 km) long. Dunes are a dominant landform on Titan. Approximately 15-20% of the surface is covered by ergs with an estimated total area of 12–18 million km making it

5106-422: The uplift of the Andes created a rain shadow on the western fringes of Chile, ocean currents and prevailing winds carried moisture away from the Chilean coast. This caused some areas of the subduction zone to be sediment-starved, causing excess friction and an increased rate of compressed coastal uplift. The main cause of the rise of the Andes is the compression of the western rim of the South American Plate due to

5180-586: The world for amphibians . The diversity of animals in the Andes is high, with almost 600 species of mammals (13% endemic), more than 1,700 species of birds (about 1/3 endemic), more than 600 species of reptiles (about 45% endemic), and almost 400 species of fish (about 1/3 endemic). The vicuña and guanaco can be found living in the Altiplano , while the closely related domesticated llama and alpaca are widely kept by locals as pack animals and for their meat and wool . The crepuscular (active during dawn and dusk) chinchillas , two threatened members of

5254-414: The world's largest reserve of the element. Early Mesozoic and Neogene plutonism in Bolivia's Cordillera Central created the Bolivian tin belt as well as the famous, now-mostly-depleted, deposits of Cerro Rico de Potosí . The Andes Mountains, initially inhabited by hunter-gatherers , experienced the development of agriculture and the rise of politically centralized civilizations , which culminated in

5328-473: The world, forming a continuous highland along the western edge of South America . The range is 8,900 km (5,530 mi) long and 200 to 700 km (124 to 435 mi) wide (widest between 18°S and 20°S latitude ) and has an average height of about 4,000 m (13,123 ft). The Andes extend from South to North through seven South American countries: Argentina , Chile , Bolivia , Peru , Ecuador , Colombia , and Venezuela . Along their length,

5402-597: The world, ranging from only a few centimeters deep in the Selima Sand Sheet of Southern Egypt, to approximately 1 m (3.3 ft) in the Simpson Desert, and 21–43 m (69–141 ft) in the Sahara. This is far shallower than ergs in prehistoric times were. Evidence in the geological record indicates that some Mesozoic and Paleozoic ergs reached a mean depth of several hundred meters. Ergs are

5476-408: Was used for the production of chicha , important to Andean native people. Currently, tobacco , cotton , and coffee are the main export crops. Coca , despite eradication programs in some countries, remains an important crop for legal local use in a mildly stimulating herbal tea , and illegally for the production of cocaine . In unirrigated land, pasture is the most common type of land use. In

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