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95-728: Along its course, the Pilcomayo silts up and splits into two main branches, North and South. After some distance, these branches rejoin to form the Lower Pilcomayo. The Pilcomayo rises in the foothills of the Andes mountain range in the Oruro Department in Bolivia , east of Lake Poopó . The Jach'a Juqhu River is considered the origin of the Pilcomayo. Upstream the Jach'a Juqhu River successively receives

190-539: 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

285-534: A higher speed than in any other part of the world. In the short term, this will cause lakes to expand and bring floods and mudflows. In the long run, the glaciers are vital lifelines for Asian rivers, including the Indus and the Ganges . Once they vanish, water supplies in those regions will be in peril. The Tibetan Plateau contains the largest area of low- latitude glaciers and is particularly vulnerable to global warming. Over

380-566: 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

475-590: 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 ,

570-671: A result of this extremely inhospitable environment, the Changtang region (together with the adjoining Kekexili region) is the least populous region in Asia and the third least populous area in the world after Antarctica and northern Greenland. The geological history of the Tibetan Plateau is closely related to that of the Himalayas. The Himalayas belong to the Alpine Orogeny and are therefore among

665-687: 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

760-415: A steady wind to blow toward the land, which brings the moist air over the ocean surface with it. Rainfall is then increased by the presence of the moist ocean air. The rainfall is stimulated by a variety of mechanisms, such as low-level air being lifted upwards by mountains, surface heating, convergence at the surface, divergence aloft, or from storm-produced outflows near the surface. When such lifting occurs,

855-621: A term usually referring to the localized, diurnal cycle of circulation near coastlines everywhere, but they are much larger in scale, stronger and seasonal. The seasonal monsoon wind shift and weather associated with the heating and cooling of the Tibetan plateau is the strongest such monsoon on Earth. Today, Tibet is an important heating surface of the atmosphere. However, during the Last Glacial Maximum , an approximately 2,400,000 square kilometres (930,000 sq mi) ice sheet covered

950-625: 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

1045-531: 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

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1140-744: 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

1235-555: 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

1330-551: 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

1425-409: Is distributed vertically through a "mixed layer" that may be 50 meters deep through the action of wind and buoyancy-generated turbulence , whereas the land surface conducts heat slowly, with the seasonal signal penetrating only a meter or so. Additionally, the specific heat capacity of liquid water is significantly greater than that of most materials that make up land. Together, these factors mean that

1520-674: Is located on the Argentine side of the border. It also forms a short part of the boundary between Argentina and Bolivia, just prior to the Argentina – Bolivia – Paraguay tripoint . The river basin is home to approximately 1.5 million people: one million in Bolivia, 300,000 in Argentina, and 200,000 in Paraguay. The Nakotoi Indian Tribe resides in the southern region of the Pilcomayo, a region located along

1615-467: 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

1710-776: Is the Qilian Mountains. The line of mountains continues east of the plateau as the Qinling , which separates the Ordos Plateau from Sichuan. North of the mountains runs the Gansu or Hexi Corridor which was the main silk-road route from China proper to the West. The plateau is a high-altitude arid steppe interspersed with mountain ranges and large brackish lakes. Annual precipitation ranges from 100 to 300 millimetres (3.9 to 11.8 in) and falls mainly as hail . The southern and eastern edges of

1805-1500: 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

1900-519: Is the world's highest and largest plateau above sea level, with an area of 2,500,000 square kilometres (970,000 sq mi). With an average elevation exceeding 4,500 metres (14,800 ft) and being surrounded by imposing mountain ranges that harbor the world's two highest summits, Mount Everest and K2 , the Tibetan Plateau is often referred to as "the Roof of the World ". The Tibetan Plateau contains

1995-404: 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

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2090-656: 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

2185-452: 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

2280-572: 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 ,

2375-523: 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

2470-549: The Changtang , is generally too high and cold to support permanent population. One of the most notable civilizations to have developed on the Tibetan Plateau is the Tibetan Empire from the 7th century to the 9th century AD. Monsoons are caused by the different amplitudes of surface temperature seasonal cycles between land and oceans. This differential warming occurs because heating rates differ between land and water. Ocean heating

2565-525: The Eurasian Plate . About 50 million years ago, this fast-moving Indo-Australian plate had completely closed the Tethys Ocean , the existence of which has been determined by sedimentary rocks settled on the ocean floor, and the volcanoes that fringed its edges. Since these sediments were light, they crumpled into mountain ranges rather than sinking to the floor. During this early stage of its formation in

2660-811: The Indian subcontinent , and to the south of Tarim Basin and Mongolian Plateau . Geopolitically, it covers most of the Tibet Autonomous Region , most of Qinghai , western half of Sichuan , Southern Gansu provinces in Western China , southern Xinjiang , Bhutan , the Indian regions of Ladakh and Lahaul and Spiti ( Himachal Pradesh ) as well as Gilgit-Baltistan in Pakistan , northwestern Nepal , eastern Tajikistan and southern Kyrgyzstan . It stretches approximately 1,000 kilometres (620 mi) north to south and 2,500 kilometres (1,600 mi) east to west. It

2755-922: The Kunlun Mountains separate the plateau from the Tarim Basin. About halfway across the Tarim the bounding range becomes the Altyn-Tagh and the Kunluns, by convention, continue somewhat to the south. In the 'V' formed by this split is the western part of the Qaidam Basin . The Altyn-Tagh ends near the Dangjin pass on the Dunhuang – Golmud road. To the west are short ranges called the Danghe, Yema, Shule, and Tulai Nanshans. The easternmost range

2850-665: 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

2945-572: 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,

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3040-664: 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

3135-582: 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

3230-563: The headwaters of the drainage basins of most of the streams and rivers in surrounding regions . This includes the three longest rivers in Asia (the Yellow , Yangtze , and Mekong ). Its tens of thousands of glaciers and other geographical and ecological features serve as a " water tower " storing water and maintaining flow . It is sometimes termed the Third Pole because its ice fields contain

3325-517: The longest continental mountain range in 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,

3420-475: 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

3515-672: The thermal low pressure caused by the heating, there was no monsoon over the Indian subcontinent . This lack of monsoon caused extensive rainfall over the Sahara , expansion of the Thar Desert , more dust deposited into the Arabian Sea , and a lowering of the biotic life zones on the Indian subcontinent. Animals responded to this shift in climate, with the Javan rusa migrating into India. In addition,

3610-402: 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

3705-405: 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

3800-405: 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

3895-446: 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:

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3990-401: 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

4085-410: 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

4180-471: 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

4275-426: 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

4370-403: 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

4465-490: The Chinese lowlands. Ice of the plateau provides a valuable window to the past. In 2015, researchers studying the Plateau reached the top of the Guliya glacier , with ice thickness of 310 m (1,020 ft), and drilled to a depth of 50 m (160 ft) in order to recover ice core samples. Due to the extremely low biomass in those 15,000-year-old samples, it had taken around 5 years of research to extract 33 viruses, of which 28 were new to science. None had survived

4560-438: 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

4655-707: The Late Palaeogene, Tibet consisted of a deep palaeovalley bounded by multiple mountain ranges rather than the more topographically uniform elevated flatland that it is today. The Tibetan Plateau's mean elevation continued to vary since its initial uplift in the Eocene; isotopic records show the plateau's altitude was around 3,000 metres above sea level around the Oligocene-Miocene boundary and that it fell by 900 metres between 25.5 and 21.6 million years ago, attributable to tectonic unroofing from east–west extension or to erosion from climatic weathering. The plateau subsequently rose by 500 to 1,000 metres between 21.6 and 20.4 million years ago. Palaeobotanical evidence indicates that

4750-512: The Nujiang Suture Zone and the Yarlung-Zangpo Suture Zone remained tropical or subtropical lowlands until the latest Oligocene or Early Miocene , enabling biotic interchange across Tibet. The age of east–west grabens in the Lhasa and Himalaya terranes suggests that the plateau's elevation was close to its modern altitude by around 14 to 8 million years ago. Erosion rates in Tibet decreased significantly around 10 million years ago. The Indo-Australian plate continues to be driven horizontally below

4845-407: 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

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4940-428: The Tibetan Plateau, which forces the plateau to move upwards; the plateau is still rising at a rate of approximately 5 mm (0.2 in) per year (although erosion reduces the actual increase in height). Much of the Tibetan Plateau is of relatively low relief. The cause of this is debated among geologists. Some argue that the Tibetan Plateau is an uplifted peneplain formed at low altitude, while others argue that

5035-425: The Tibetan plateau from around 200,000 to 40,000 years ago, according to a study published in Nature . Nomads on the Tibetan Plateau and in the Himalayas are the remainders of nomadic practices historically once widespread in Asia and Africa. Pastoral nomads constitute about 40% of the ethnic Tibetan population. The presence of nomadic peoples on the plateau is predicated on their adaptation to survival on

5130-433: The air cools due to expansion in lower pressure, which in turn produces condensation and precipitation. In winter, the land cools off quickly, but the ocean maintains the heat longer. The hot air over the ocean rises, creating a low-pressure area and a breeze from land to ocean while a large area of drying high pressure is formed over the land, increased by wintertime cooling. Monsoons are similar to sea and land breezes ,

5225-402: 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

5320-399: 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

5415-478: 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

5510-475: The elevation and low precipitation. The Tibetan Plateau hosts the Tibetan wolf , and species of snow leopard , wild yak , wild ass , cranes, vultures, hawks, geese, snakes, and water buffalo . One notable animal is the high-altitude jumping spider , that can live at elevations of over 6,500 metres (21,300 ft). Ecoregions found on the Tibetan Plateau, as defined by the World Wide Fund for Nature , are as follows: Extinct humans ( Denisovans ) lived on

5605-501: 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

5700-519: 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

5795-411: The extraction process. Phylogenetic analysis suggests those viruses infected plants or other microorganisms. The Tibetan Plateau contains the world's third-largest store of ice. Qin Dahe, the former head of the China Meteorological Administration , issued the following assessment in 2009: Temperatures are rising four times faster than elsewhere in China, and the Tibetan glaciers are retreating at

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5890-423: 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

5985-401: 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

6080-555: 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

6175-423: The glaciers in Tibet created meltwater lakes in the Qaidam Basin , the Tarim Basin , and the Gobi Desert , despite the strong evaporation caused by the low latitude. Silt and clay from the glaciers accumulated in these lakes; when the lakes dried at the end of the ice age, the silt and clay were blown by the downslope wind off the Plateau. These airborne fine grains produced the enormous amount of loess in

6270-447: 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

6365-400: The heat capacity of the layer participating in the seasonal cycle is much larger over the oceans than over land, with the consequence that the land warms and cools faster than the ocean. In turn, air over the land warms faster and reaches a higher temperature than does air over the ocean. The warmer air over land tends to rise, creating an area of low pressure . The pressure anomaly then causes

6460-453: 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

6555-467: 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

6650-439: 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

6745-405: The largest reserve of fresh water outside the polar regions. The impact of climate change on the Tibetan Plateau is of ongoing scientific interest. The Tibetan Plateau is surrounded by the massive mountain ranges of high-mountain Asia . The plateau is bordered to the south by the inner Himalayan range , to the north by the Kunlun Mountains , which separate it from the Tarim Basin , and to

6840-538: The late 19th century. Men of this tribe are generally tall and skinny, built like hunters or warriors, whereas women are short in size. The Natokoi dress in a rug, fastened around the waist-line. 25°21′S 57°40′W  /  25.350°S 57.667°W  / -25.350; -57.667 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

6935-404: The latter, the plateau is affected by distributed deformation resulting from flow within the crust. The Tibetan Plateau supports a variety of ecosystems, most of them classified as montane grasslands. While parts of the plateau feature an alpine tundra -like environment, other areas feature monsoon-influenced shrublands and forests. Species diversity is generally reduced on the plateau due to

7030-428: The low relief stems from erosion and infill of topographic depressions that occurred at already high elevations. The current tectonics of the plateau are also debated. The best-regarded explanations are provided by the block model and the alternative continuum model. According to the former, the crust of the plateau is formed of several blocks with little internal deformation separated by major strike-slip faults . In

7125-509: 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

7220-621: The names Aguas Calientes and Kachi Mayu. From the confluence with the Chillawa (Chillahua) , the river is called Pilcomayo. From there, it flows in a southeasterly direction through Chuquisaca and Tarija departments, passes through the Argentine province of Formosa and the Gran Chaco plains of Paraguay , forming most of the border between these two countries before it joins the Paraguay River near Asunción . The Río Pilcomayo National Park

7315-561: 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,

7410-660: The northeast by the Qilian Mountains , which separate the plateau from the Hexi Corridor and Gobi Desert . To the east and southeast the plateau gives way to the forested gorge and ridge geography of the mountainous headwaters of the Salween , Mekong , and Yangtze rivers in northwest Yunnan and western Sichuan (the Hengduan Mountains ). In the west, the curve of the rugged Karakoram range of northern Kashmir embraces

7505-555: The plateau. Due to its great extent, this glaciation in the subtropics was an important element of radiative forcing . With a much lower latitude, the ice in Tibet reflected at least four times more radiation energy per unit area into space than ice at higher latitudes . Thus, while the modern plateau heats the overlying atmosphere, during the Last Ice Age it helped to cool it. This cooling had multiple effects on regional climate. Without

7600-406: The plateau. The Indus River originates in the western Tibetan Plateau in the vicinity of Lake Manasarovar . The Tibetan Plateau is bounded in the north by a broad escarpment where the altitude drops from around 5,000 metres (16,000 ft) to 1,500 metres (4,900 ft) over a horizontal distance of less than 150 kilometres (93 mi). Along the escarpment is a range of mountains. In the west,

7695-530: The principal mines of the Spanish Empire in the New World. Río de la Plata and Argentina derive their names from the silver of Potosí. Tibetan Plateau The Tibetan Plateau , also known as Qinghai–Tibet Plateau and Qing–Zang Plateau , is a vast elevated plateau located at the intersection of Central , South , and East Asia . . Geographically, it is located to the north of Himalayas and

7790-402: 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

7885-613: The river in central Paraguay. The aborigines of this tribe are descendants of the highly renowned Redskin Tribe. The Natokoi treated all neighbors as enemies, but none more so than the Tobas Tribe and the Nimká Tribe, their respective neighbors to the southwest and northeast. Guerrilla warfare has long existed between the tribes, isolating the tribe from direct intercourse with the European settlers in

7980-460: 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

8075-717: 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

8170-511: The steppe have grasslands that can sustainably support populations of nomadic herdsmen, although frost occurs for six months of the year. Permafrost occurs over extensive parts of the plateau. Proceeding to the north and northwest, the plateau becomes progressively higher, colder, and drier, until reaching the remote Changtang region in the northwestern part of the plateau. Here the average altitude exceeds 5,000 metres (16,000 ft) and winter temperatures can drop to −40 °C (−40 °F). As

8265-526: 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

8360-562: 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,

8455-452: 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

8550-472: 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

8645-637: 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

8740-400: The world's grassland by raising livestock rather than crops, which are unsuitable to the terrain. Archaeological evidence suggests that the earliest human occupation of the plateau occurred between 30,000 and 40,000 years ago. Since colonization of the Tibetan Plateau, Tibetan culture has adapted and flourished in the western, southern, and eastern regions of the plateau. The northern portion,

8835-465: 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

8930-588: The younger mountain ranges on the planet, consisting mostly of uplifted sedimentary and metamorphic rock . Their formation is a result of a continental collision or orogeny along the convergent boundary between the Indo-Australian Plate and the Eurasian Plate . The collision began in the Upper Cretaceous period about 70 million years ago, when the north-moving Indo-Australian Plate , moving at about 15 cm (6 in) per year, collided with

9025-408: 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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