Transverse Valleys
The Transverse Valleys are a group of transverse valleys in the semi-arid northern Chile. They run from east to west, being among the most prominent geographical features in the regions they cross, they are located in the Chilean regions of Valparaíso, Atacama. They share some characteristics, such as reaching the Pacific Ocean without passing through an Intermediate Depression, being rather deep and dissecting the landscape, concentrating most agriculture and population in the areas through which they pass, being intensively cultivated, they are one of the defining elements the Chilean natural region of Norte Chico. The area of the Transverse Valleys spans a length of 600 km from north to south. Agriculture in Chile Astronomy in Chile Calchaquí Valleys Chilean Matorral Diaguita Flowering desert Sierras Pampeanas
Andes
The Andes or Andean Mountains are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. This range is about 7,000 km long, about 200 to 700 km wide, of an average height of about 4,000 m; the Andes extend from north to south through seven South American countries: Venezuela, Ecuador, Bolivia and Argentina. Along their length, 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, Medellín, Sucre, Mérida 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: the Tropical Andes, the Dry Andes, the Wet Andes. The Andes Mountains are the world's highest mountain range outside Asia; the highest mountain outside Asia, Argentina's Mount Aconcagua, rises to an elevation of about 6,961 m 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 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; the Andes are part of the American Cordillera, a chain of mountain ranges that consists of an continuous sequence of mountain ranges that form the western "backbone" of North America, Central America, South America and Antarctica. The etymology of the word Andes has been debated; the majority consensus is that it derives from the Quechua word anti, which means "east" as in Antisuyu, one of the four regions of the Inca Empire. The Andes can be divided into three sections: The Southern Andes in Chile. In the northern part of the Andes, the isolated Sierra Nevada de Santa Marta range is considered to be part of the Andes; the term cordillera comes from the Spanish word "cordel", meaning "rope".
The Andes range is about 200 km wide throughout its length, except in the Bolivian flexure where it is about 640 kilometres wide. The Leeward Antilles islands Aruba and Curaçao, which lie in the Caribbean Sea off the coast of Venezuela, were 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 a Mesozoic–Tertiary orogenic belt of mountains along the Pacific Ring of Fire, 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, caused by the subduction of oceanic crust beneath the South American Plate, it is the result of a convergent plate boundary between the Nazca Plate and the South American Plate The main cause of the rise of the Andes is the compression of the western rim of the South American Plate due to the subduction of the Nazca Plate and the Antarctic Plate.
To the east, the Andes range is bounded by several sedimentary basins, such as Orinoco, Amazon Basin, Madre de Dios and 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, 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 a less rugged topography; the Andes Mountains contain large quantities of iron ore located in many mountains within the range. The Andean orogen has a series of 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 segment north and south of the orocline have been rotated 15° to 20° counter clockwise and clockwise respectively.
The Bolivian Orocline area overlaps with the area of maximum width of the Altiplano Plateau and according to Isacks 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 or Maipo Transition Zone located between 30° S and 38°S with a break in trend at 33° S. Near the southern tip of the Andes lies 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 the South American part of Gondwana. The formation of the modern Andes began with the events of the Triassic when Pangaea began the break up 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 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 and erosion. Tectonic forces above the subduction zone al
Atacama Region
This article is about the Atacama Region. The Atacama Region is one of Chile's 16 first order administrative divisions, it comprises three provinces: Copiapó and Huasco. It is bordered to the north by Antofagasta, to the south by Coquimbo, to east with Provinces of Catamarca, La Rioja and San Juan of Argentina, to the west by the Pacific Ocean; the regional capital Copiapó is located at 806 km north of the country's capital of Santiago. The region occupies the southern portion of the Atacama Desert, the rest of the desert is distributed among the other regions of Norte Grande The Atacama Region is the third least populated region of the country, after Aysen and Magallanes. Of its total population, over 50 % are located in the cities of Vallenar; the largest cities are Copiapó, Caldera, Chañaral, El Salvador Tierra Amarilla, Diego de Almagro. The original inhabitants of this area, the Diaguitas and Changos valued its mineral wealth. Since the 19th century, copper and gold have brought prosperity.
The region experienced a boom when the Chañarcillo silver mine was discovered in 1832. For many years, this was the world's third largest silver mine. Much of the region is desert, encompasses considerable mineral resources. Numerous flora and fauna species are found in the Atacama Region. One subspecies of the lesser rhea, known by the scientific name Rhea pennata tarapacensis, is a notable large terrestrial bird in this region, which subspecies is considered endangered; the diminished numbers of this bird are due to prehistoric and modern hunting but more due to agricultural land conversion in order to feed the expanding human population. Mining accounts for 90 % of its exports. Moreover, various geological surveys have identified new deposits. Iron ore mining is the most dynamic activity and there are numerous small-scale mines, which sell their output to ENAMI for processing at its Paipote smelter; the region's main copper deposit is Candelaria, which produces around 200,000 tonnes per year and is controlled by Phelps Dodge, an international corporation.
The next in size is El Salvador, owned by CODELCO, with an annual output of around 81,000 tonnes. Both mines export through the port of Chañaral. Over recent decades, fresh fruit emerged as regional export item, when the Copiapó and Huasco valleys joined Chile’s fruit-growing boom, they enjoy a comparative advantage because, thanks to the sunny climate, fruit ripens earlier than in the rest of the country and reaches northern hemisphere markets first. Grapes are the main crop and, on a smaller scale, tomatoes, onions, broad beans, citrus fruits, apricots and flowers; the region's organic wealth, its clear waters and sheltered bays, together with its entrepreneurial experience, favor the development of aquaculture. Species produced include the northern scallop and Chilean oysters, turbot and different varieties of mussels. Other products with more value added include boned fish fillets and salted fish and fishburgers; the unique weather conditions in the Atacama desert, with rare cloudy days, are ideal for solar power generation.
Many PV and CSP plants are being built in this area. Flag of Atacama Teresa Moreno and Wes Gibbons. 2007. The geology of Chile, Geological Society of London, 414 pages Gobierno Regional de Atacama Official website
Nevado Tres Cruces
Nevado Tres Cruces is a massif of volcanic origin in the Andes Mountains on the border of Argentina and Chile. It has two main summits, Tres Cruces Sur at 6,748 metres and Tres Cruces Centro at 6,629 m and a third more minor summit, Tres Cruces Norte 6,206 m. Tres Cruces Sur is the sixth highest mountain in the Andes; the area was first surveyed in 1883 by Francisco San Román and the Nevado Tres Cruces National Park was established in 1994. The volcano has an extended history of activity, going back at least 1.5 million years. A number of lava domes surround a number of craters lie on its summits; the main volcano is of rhyodacitic composition and has generated two major ignimbritic eruptions, one 1.5 million years ago and a second 67,000 years ago. The last eruption was 28,000 years ago, but the volcano is a candidate source for a Holocene eruption and it may become active in the future; the area has a desert climate, with nighttime temperatures below freezing and precipitation less than 29±14 mm in the local summer that sublimates away, resulting in a lack of surface runoff and a barren landscape.
The mean annual temperature is -2±4 degrees Celsius. The area is persistently windy; the snowline altitude in the area is 5,800 m, higher than the Pleistocene altitude of 5,500 m. 55 small relic glaciers with surfaces of less than 1 square kilometre exist above 5,500 m with moraines visible above 4,400 m. In 2000 a total ice surface of 1.1 km2 was reported on Tres Cruces. The whole complex has been active for 1.5 mya and has generated two large scale pyroclastic eruptions, a first one 1.5 mya occurred on the western side of the volcano. It is thin and covers Pliocene lavas. Otherwise, rhyodacitic lava flows, lava domes and various ash and tephra deposits belong to this volcano; the three main volcanoes of the massif - Tres Cruces Sur, Tres Cruces Centro and Tres Cruces Norte formed along a local fault zone. Tres Cruces Sur and Tres Cruces Centro are the sixth and eleventh highest mountains in South America; the massif has an extent of 10 km × 5 km. The principal edifices are steep, rising 800 -- 1,600 m above their bases.
The northern cone has a crater 1 km wide. The central edifice is inclined westward; the southern edifice is formed from an older western structure with two small craters and a glacial cirque, an eastern edifice with a summit lava dome 2 km wide and basal lava flows. A cirque contains a small glacier; the whole edifice and the adjacent Miocene El Plateado volcano, as well as the western flank of neighbouring Ojos del Salado volcano, are covered with a thick layer of pumiceous ash fall produced by the collapse of an eruption column. Pliocene volcanic chain Cristi and Rodrigo north and Puntiagudo south is buried beneath the massif. Tomographic analysis of the area has indicated the presence of a large high-attenuation zone in the crust beneath Tres Cruces and the neighbouring Ojos del Salado volcano, which may indicate ongoing or incipient melting of the underlying crust. Two minor lava domes La Espinilla and El Indio are present. La Espinilla formed within the crater of an explosive eruption; this dome formed 168 ± 6 ka K-Ar.
El Indio is located on the side of La Espinilla away from the main massif and is larger and older than Espinilla. Other older lava domes lie on the western flank. A major dacitic lava dome lies on the northwestern side of the massif, the vent is buried by younger deposits; the lava display has been K-Ar dated 1.4 ± 0.4 mya. Activity in the southernmost volcano has been dated at 280,000±22,000 years ago; the complex is linked to the eruption of the Tres Cruces ignimbrite 67,000 years ago known as Pampa Blanca. This ignimbrite is well exposed in the valley which separates the Tres Cruces and Ojos del Salado volcanoes, assuming thicknesses of 100 m with a basal flow 15 m thick; the youngest activity occurred 28,000 years ago and formed the summit lava dome of the southernmost volcano. Tres Cruces may have erupted during the Holocene; this eruption affected the environment and societies of the Fiambalá area. The volcano has an approximate rock generation rate of 0.13 km3/ka, lower than other arc associated volcanoes.
With eruptive episodes being separated by gaps of about 40,000 years between the last episodes, dangerous eruptive activity in the future is possible. However, the region surrounding the volcano is thinly populated, so major damage to infrastructure or danger to human life is unlikely. Biggar, John. Andes: A guide for climbers. Castle Douglas: Andes. P. 183. ISBN 978-0953608720. Retrieved 22 November 2015. Global Volcanism Program: Nevado Tres Cruces Andes Handbook Tres Cruces
Desertification
Desertification is a type of land degradation in which a dry area of land becomes a desert losing its bodies of water as well as vegetation and wildlife. It is caused by a variety of factors, such as through climate change and through the overexploitation of soil through human activity; when deserts appear automatically over the natural course of a planet's life cycle it can be called a natural phenomenon. Desertification is a significant global ecological and environmental problem with far reaching consequences on socio-economic and political conditions. Considerable controversy exists over the proper definition of the term "desertification" for which Helmut Geist has identified more than 100 formal definitions; the most accepted of these is that of the Princeton University Dictionary which defines it as "the process of fertile land transforming into desert as a result of deforestation, drought or improper/inappropriate agriculture". Desertification has been neatly defined in the text of the United Nations Convention to Combat Desertification as "land degradation in arid, semi-arid and dry sub-humid regions resulting from various factors, including climatic variations and human activities."Another major contribution to the controversy comes from the sub-grouping of types of desertification.
Spanning from the vague yet shortsighted view as the "man-made-desert" to the broader yet less focused type as the "Non-pattern-Desert". The earliest known discussion of the topic arose soon after the French colonization of West Africa, when the Comité d'Etudes commissioned a study on desséchement progressif to explore the prehistoric expansion of the Sahara Desert; the world's most noted deserts have been formed by natural processes interacting over long intervals of time. During most of these times, deserts have shrunk independent of human activities. Paleodeserts are large sand seas now inactive because they are stabilized by vegetation, some extending beyond the present margins of core deserts, such as the Sahara, the largest hot desert. Desertification has played a significant role in human history, contributing to the collapse of several large empires, such as Carthage and the Roman Empire, as well as causing displacement of local populations. Historical evidence shows that the serious and extensive land deterioration occurring several centuries ago in arid regions had three epicenters: the Mediterranean, the Mesopotamian Valley, the Loess Plateau of China, where population was dense.
Drylands occupy 40–41% of Earth’s land area and are home to more than 2 billion people. It has been estimated that some 10–20% of drylands are degraded, the total area affected by desertification being between 6 and 12 million square kilometres, that about 1–6% of the inhabitants of drylands live in desertified areas, that a billion people are under threat from further desertification; as of 1998, the then-current degree of southward expansion of the Sahara was not well known, due to a lack of recent, measurable expansion of the desert into the Sahel at the time. The impact of global warming and human activities are presented in the Sahel. In this area, the level of desertification is high compared to other areas in the world. All areas situated in the eastern part of Africa are characterized by a dry climate, hot temperatures, low rainfall. So, droughts are the rule in the Sahel region; some studies have shown that Africa has lost 650,000 km² of its productive agricultural land over the past 50 years.
The propagation of desertification in this area is considerable. Some statistics have shown that since 1900 the Sahara has expanded by 250 km to the south over a stretch of land from west to east 6,000 km long; the survey, done by the research institute for development, had demonstrated that this means dryness is spreading fast in the Sahelian countries. 70% of the arid area has deteriorated and water resources have disappeared, leading to soil degradation. The loss of topsoil means that plants cannot take root and can be uprooted by torrential water or strong winds; the United Nations Convention says that about six million Sahelian citizens would have to give up the desertified zones of sub-Saharan Africa for North Africa and Europe between 1997 and 2020. Another major area, being impacted by desertification is the Gobi Desert; the Gobi desert is the fastest moving desert on Earth. This has destroyed many villages in its path. Photos show that the Gobi Desert has expanded to the point the entire nation of Croatia could fit inside its area.
This is causing a major problem for the people of China. They will soon have to deal with the desert. Although the Gobi Desert itself is still a distance away from Beijing, reports from field studies state there are large sand dunes forming only 70 km outside the city; as the desertification takes place, the landscape may progress through different stages and continuously transform in appearance. On sloped terrain, desertification can create larger empty spaces over a large strip of land, a phenomenon known as "Brousse tigrée". A mathematical model of this phenomenon proposed by C. Klausmeier attributes this patterning to dynamics in plant-water interaction. One outcome of this observation suggests an optimal plan
Pisco
Pisco is a colorless or yellowish-to-amber colored brandy produced in winemaking regions of Peru and Chile. Made by distilling fermented grape juice into a high-proof spirit, it was developed by 16th century Spanish settlers as an alternative to orujo, a pomace brandy, being imported from Spain, it had the advantages of being produced from abundant domestically grown fruit and reducing the volume of alcoholic beverages transported to remote locations. Annual pisco production in 2013 reached 9.5 million litres in Peru. Chile is the main importer of pisco from Peru: 34% of the pisco produced in Peru is exported to Chile; the oldest use of the word pisco to denote Peruvian aguardiente dates from 1764. The beverage may have acquired its Quechua name from the Peruvian town of Pisco – once an important colonial port for the exportation of viticultural products – located on the coast of Peru in the valley of Pisco, by the river with the same name. From there, "Aguardiente de Pisco" was exported to Europe Spain, where the beverage's name was abbreviated to "Pisco".
The Viennese newspaper Wiener Zeitung, in 1835 reports on the Peruvian spirit made from Italia grapes: A large quantity of a spirit known as Pisco de Italia, imported from Peru, was consumed in Chile. But since the import duties are so high, a similar grape with large oval berries has been used to produce a similar drink, which has completely displaced the Peruvian. In the Medical Lexikon of Robley Dunglison it is stated that, following observations of Swiss Johann Jakob von Tschudi: In Peru, the common brandy obtained from grapes is the Aguardiente de Pisco, so called because shipped at the port of Pisco. Chilean linguist Rodolfo Lenz said that the word pisco was used all along the Pacific coast of the Americas from Arauco to Guatemala, that the word would be of Quechua origin meaning "bird"; this claim is disputed by Chilean linguist Mario Ferreccio Podesta, who supports the former Real Academia Española etymology according to which pisco was a word for a mud container. However, the Real Academia Española supported Lenz's theory, underlines the Quechua origin.
Other origins for the word pisco have been explored, including a Mapudungun etymology where "pishku" has been interpreted as "something boiled in a pot," which would relate to the concept of burned wine. The term influenced the Mexican Spanish use of the slang term pisto to denote distilled spirits generally. Unlike the land in most of the Viceroyalty of New Spain, where only few vineyards were established, some locations in the Viceroyalty of Peru were quite suitable for growing grape vines. By 1560, Peru was producing wine for commerce, it grew sufficiently strong and threatening to the Spanish mercantilist policies that in 1595 the Spanish Crown banned the establishment of new vineyards in the Americas to protect the exports of its native wine industry. As further protectionist measures, the Crown forbade exportation of Peruvian wine to Panama in 1614 and Guatemala in 1615. Distillation of the wine into pisco began in earnest around the turn of the 17th century in response to these pressures.
Until the early 18th century, most aguardiente was still used to fortify wine, in order to prevent its oxidation, rather than drunk on its own. This method of conservation corresponds with fortified wines that were shipped to Italy and Spain from other parts of the world. In the 17th century production and consumption of wine and pisco were stimulated by the mining activities in Potosí, by the largest city in the New World; the entire southern coast of Peru was struck by the 1687 Peru earthquake, which destroyed the cities of Villa de Pisco and Ica. Wine cellars in the affected area collapsed and mud containers broke, causing the nation's wine-growing industry to collapse. Still, in the early 18th century wine production in Peru exceeded that of pisco. By 1764, pisco production dwarfed that of wine, representing 90% of the grape beverages prepared. With the suppression of the Society of Jesus in Spanish America, Jesuit vineyards were auctioned off, new owners did not have the same expertise as the Jesuits – leading to a production decline.
In the late 18th century the Spanish Crown allowed the production of rum in Peru, cheaper and of lower quality than pisco. In the 19th century demand for cotton in industrialized Europe caused many Peruvian winegrowers to shift away from vineyards to more lucrative cotton planting, contributing further to the decline of wine production and the pisco industry which depended on it; this was true during the time of the American Civil War when cotton prices skyrocketed due to the Blockade of the South and its cotton fields. Pisco was popular in the US, in San Francisco and nearby areas of California during the Gold Rush in the late 1800s and early 1900s. Peruvian Pisco must be made in the country's five official D. O. departments—Lima, Arequipa and Tacna — established in 1991 by the government. In Peru, pisco is produced only using copper pot stills, like single malt Scotch whiskies, rather than continuous stills like most vodkas. Unlike the Chilean
Irrigation
Irrigation is the application of controlled amounts of water to plants at needed intervals. Irrigation helps to grow agricultural crops, maintain landscapes, revegetate disturbed soils in dry areas and during periods of less than average rainfall. Irrigation has other uses in crop production, including frost protection, suppressing weed growth in grain fields and preventing soil consolidation. In contrast, agriculture that relies only on direct rainfall is referred to as rain-fed or dry land farming. Irrigation systems are used for cooling livestock, dust suppression, disposal of sewage, in mining. Irrigation is studied together with drainage, the removal of surface and sub-surface water from a given area. Irrigation has been a central feature of agriculture for over 5,000 years and is the product of many cultures, it was the basis for economies and societies across the globe, from Asia to the Southwestern United States. Archaeological investigation has found evidence of irrigation in areas lacking sufficient natural rainfall to support crops for rainfed agriculture.
The earliest known use of the technology dates to the 6th millennium BCE in Khuzistan in the south-west of present-day Iran. Irrigation was used as a means of manipulation of water in the alluvial plains of the Indus valley civilization, the application of it is estimated to have begun around 4500 BC and drastically increased the size and prosperity of their agricultural settlements; the Indus Valley Civilization developed sophisticated irrigation and water-storage systems, including artificial reservoirs at Girnar dated to 3000 BCE, an early canal irrigation system from c. 2600 BCE. Large-scale agriculture was practiced, with an extensive network of canals used for the purpose of irrigation. Farmers in the Mesopotamian plain used irrigation from at least the third millennium BCE, they developed perennial irrigation watering crops throughout the growing season by coaxing water through a matrix of small channels formed in the field. Ancient Egyptians practiced basin irrigation using the flooding of the Nile to inundate land plots, surrounded by dykes.
The flood water remained until the fertile sediment had settled before the engineers returned the surplus to the watercourse. There is evidence of the ancient Egyptian pharaoh Amenemhet III in the twelfth dynasty using the natural lake of the Faiyum Oasis as a reservoir to store surpluses of water for use during dry seasons; the lake swelled annually from the flooding of the Nile. The Ancient Nubians developed a form of irrigation by using a waterwheel-like device called a sakia. Irrigation began in Nubia some time between the third and second millennia BCE, it depended upon the flood waters that would flow through the Nile River and other rivers in what is now the Sudan. In sub-Saharan Africa irrigation reached the Niger River region cultures and civilizations by the first or second millennium BCE and was based on wet-season flooding and water harvesting. Evidence of terrace irrigation occurs in pre-Columbian America, early Syria and China. In the Zana Valley of the Andes Mountains in Peru, archaeologists have found remains of three irrigation canals radiocarbon-dated from the 4th millennium BCE, the 3rd millennium BCE and the 9th century CE.
These canals provide the earliest record of irrigation in the New World. Traces of a canal dating from the 5th millennium BCE were found under the 4th-millennium canal. Ancient Persia used irrigation as far back as the 6th millennium BCE to grow barley in areas with insufficient natural rainfall; the Qanats, developed in ancient Persia about 800 BCE, are among the oldest known irrigation methods still in use today. They are now found in the Middle East and North Africa; the system comprises a network of vertical wells and sloping tunnels driven into the sides of cliffs and of steep hills to tap groundwater. The noria, a water wheel with clay pots around the rim powered by the flow of the stream, first came into use at about this time among Roman settlers in North Africa. By 150 BCE the pots were fitted with valves to allow smoother filling as they were forced into the water; the irrigation works of ancient Sri Lanka, the earliest dating from about 300 BCE in the reign of King Pandukabhaya, under continuous development for the next thousand years, were one of the most complex irrigation systems of the ancient world.
In addition to underground canals, the Sinhalese were the first to build artificial reservoirs to store water. These reservoirs and canal systems were used to irrigate paddy fields, which require a lot of water to cultivate. Most of these irrigation systems still exist undamaged up to now, in Anuradhapura and Polonnaruwa, because of the advanced and precise engineering; the system was further extended during the reign of King Parakrama Bahu. The oldest known hydraulic engineers of China were Sunshu Ao of the Spring and Autumn period and Ximen Bao of the Warring States period, both of whom worked on large irrigation projects. In the Sichuan region belonging to the state of Qin of ancient China, the Dujiangyan Irrigation System devised by the Qin Chinese hydrologist and irrigation engineer Li Bing was built in 256 BCE to irrigate a vast area of farmland that today still supplies water. By the 2nd century AD, during the Han Dynasty, the Chinese used chain pumps which lifted water from a lower elevation to a higher one.
These were powered by manual foot-pedal, hydraulic waterwheels, or rotating mechanical wheels pulled by oxen. The water was used for public works, providing water for urban residential quarters and palace gardens, bu
One or more of the preceding sentences incorporates text from a publication now in the public domain: Chisholm, Hugh, ed. (1911). "Chile". Encyclopædia Britannica. 6 (11th ed.). Cambridge University Press. p. 142.
One or more of the preceding sentences incorporates text from a publication now in the 
This article incorporates public domain material from the Library of Congress Country Studies website http://lcweb2.loc.gov/frd/cs/.
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