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Sajsi
Sajsi is the name of an ancient lake in the Andes The existence of ancient lakes in the Altiplano was proposed as early as 1882. At first, a Lake Minchin was identified with ages of 30,000 years or older; later additional lake cycles were recognized. The minor ones include Inca Huasi, Salinas and Coipasa. The major ones include Lake Tauca and Ouki. Because of this, it was proposed that Lake Minchin was actually a combination of several different ancient lakes. This lake occupied the area of the current Salar de Uyuni; it also covered the Salar de Coipasa but it is not clear whether and how it extended in the Lake Poopo. Its waters reached altitudes of and its depth did not exceed . A sample dated 23,700 ± 2,600 years ago by uranium-thorium dating indicates that lake levels at that point were about deep in the Uyuni basin. Water levels subsequently decreased to less than above the present day levels before Lake Tauca formed, however both the timing and the history of wat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Tauca
Lake Tauca is a former lake in the Altiplano of Bolivia. It is also known as Lake Pocoyu for its constituent lakes: Lake Poopó, Salar de Coipasa and Salar de Uyuni. The lake covered large parts of the southern Altiplano between the Eastern Cordillera and the Western Cordillera, covering an estimated of the basins of present-day Lake Poopó and the Salars of Uyuni, Coipasa and adjacent basins. Water levels varied, possibly reaching in altitude. The lake was saline. The lake received water from Lake Titicaca, but whether this contributed most of Tauca's water or only a small amount is controversial; the quantity was sufficient to influence the local climate and depress the underlying terrain with its weight. Diatoms, plants and animals developed in the lake, sometimes forming reef knolls. The duration of Lake Tauca's existence is uncertain. Research in 2011 indicated that the rise in lake levels began 18,500 BP, peaking 16,000 and 14,500 years ago. About 14,200 years ago, la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inca Huasi (ancient Lake)
Inca Huasi was a paleolake in the Andes. It was named by a research team in 2006. It existed about 46,000 years ago in the Salar de Uyuni basin. Water levels during this episode rose by about . Overall, this lake cycle was short and not deep, with water levels reaching a height of . The lake would have had a surface of . Most water was contributed to it by the Uyuni-Coipasa drainage basin, with only minimal contributions from Lake Titicaca. Changes in the South American monsoon may have triggered its formation. Radiocarbon dates on tufa which formed in Lake Inca Huasi were dated at 45,760 ± 440 years ago. Uranium-thorium dating has yielded ages between 45,760 and 47,160 years. Overall the lake existed between 46,000 and 47,000 years ago. The Inca Huasi cycle coincides with the marine isotope stage 3, the formation of a deep lake in the Laguna Pozuelos basin and the expansion of glaciers in several parts of South America including the Puna. This lake cycle took part during a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andes
The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S latitude), and has an average height of about . The Andes extend from north to south through seven South American countries: Venezuela, Colombia, Ecuador, Peru, Bolivia, Chile, 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, 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: the Tropical Andes, the Dry Andes, and the Wet Andes. The Andes Mountains are the highest m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Last Glacial Maximum
The Last Glacial Maximum (LGM), also referred to as the Late Glacial Maximum, was the most recent time during the Last Glacial Period that ice sheets were at their greatest extent. Ice sheets covered much of Northern North America, Northern Europe, and Asia and profoundly affected Earth's climate by causing drought, desertification, and a large drop in sea levels. Based on changes in position of ice sheet margins dated via terrestrial cosmogenic nuclides and radiocarbon dating, growth of ice sheets commenced 33,000 years ago and maximum coverage was between 26,500 years and 19–20,000 years ago, when deglaciation commenced in the Northern Hemisphere, causing an abrupt rise in sea level. Decline of the West Antarctica ice sheet occurred between 14,000 and 15,000 years ago, consistent with evidence for another abrupt rise in the sea level about 14,500 years ago. Glacier fluctuations around the Strait of Magellan suggest the peak in glacial surface area was constrained to betwee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Of Bolivia
The geology of Bolivia comprises a variety of different lithologies as well as tectonic and sedimentary environments. On a synoptic scale, geological units coincide with topographical units. The country is divided into a mountainous western area affected by the subduction processes in the Pacific and an eastern lowlands of stable platforms and shields. The Bolivian Andes is divided into three main ranges; these are from west to east: the Cordillera Occidental that makes up the border to Chile and host several active volcanoes and geothermal areas, Cordillera Central (in some contexts also called Cordillera Oriental) once extensively mined for silver and tin and the relatively low Cordillera Oriental that rather than being a range by its own is the eastern continuation of the Central Cordillera as a fold and thrust belt. Between the Occidental and Central Cordillera the approximately 3,750-meter-high Altiplano high plateau extends. This basin hosts several freshwater lakes, incl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Former Lakes Of South America
A former is an object, such as a template, gauge or cutting die, which is used to form something such as a boat's hull. Typically, a former gives shape to a structure that may have complex curvature. A former may become an integral part of the finished structure, as in an aircraft fuselage, or it may be removable, being using in the construction process and then discarded or re-used. Aircraft formers Formers are used in the construction of aircraft fuselage, of which a typical fuselage has a series from the nose to the empennage, typically perpendicular to the longitudinal axis of the aircraft. The primary purpose of formers is to establish the shape of the fuselage and reduce the column length of stringers to prevent instability. Formers are typically attached to longerons, which support the skin of the aircraft. The "former-and-longeron" technique (also called stations and stringers) was adopted from boat construction, and was typical of light aircraft built until the ad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andean Geology
''Andean Geology'' (formerly ''Revista Geológica de Chile'') is a peer-reviewed scientific journal published three times per year by the National Geology and Mining Service, Chile's geology and mining agency. The journal covers the field of geology and related earth sciences, primarily on issues that are relevant to South America, Central America, and Antarctica with a particular focus on the Andes. The journal was established in 1974 and articles are published in English and Spanish. The editor-in-chief An editor-in-chief (EIC), also known as lead editor or chief editor, is a publication's editorial leader who has final responsibility for its operations and policies. The highest-ranking editor of a publication may also be titled editor, managing ... is Waldo Vivallo (National Geology and Mining Service). References External links * Geology journals Geology of South America Geology of Antarctica Publications established in 1974 Andes Multilingual journals Open ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gran Chaco
The Gran Chaco or Dry Chaco is a sparsely populated, hot and semiarid lowland natural region of the Río de la Plata basin, divided among eastern Bolivia, western Paraguay, northern Argentina, and a portion of the Brazilian states of Mato Grosso and Mato Grosso do Sul, where it is connected with the Pantanal region. This land is sometimes called the Chaco Plain. Toponymy The name Chaco comes from a word in Quechua, an indigenous language from the Andes and highlands of South America. The Quechua word ''chaqu'' meaning "hunting land" comes probably from the rich variety of animal life present throughout the entire region. Geography The Gran Chaco is about 647,500 km² (250,000 sq mi) in size, though estimates differ. It is located west of the Paraguay River and east of the Andes, and is mostly an alluvial sedimentary plain shared among Paraguay, Bolivia, and Argentina. It stretches from about 17 to 33°S latitude and between 65 and 60°W longitude, though estimate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cordillera Occidental (Bolivia)
Topographic map of Bolivia showing (east to west) plains of Sub-Andean Zone in red, Eastern_Cordillera_in_white,_Altiplano.html" ;"title="Cordillera Oriental (Bolivia)">Eastern Cordillera in white, Altiplano">Cordillera Oriental (Bolivia)">Eastern Cordillera in white, Altiplano in gray, and Western Cordillera in white The Cordillera Occidental or Western Cordillera of Bolivia is part of the Andes (that is also part of the American Cordillera), a mountain range characterized by volcanic activity, making up the natural border with Chile and starting in the north with Juqhuri and ending in the south at the Licancabur volcano, which is on the southern limit of Bolivia with Chile. The border goes through the innominated point located at two-thirds of elevation of Licancabur's northeastern slope at the southwestermost point of Bolivia at 22° 49' 41" south and 67° 52' 35" west. The climate of the region is cold and inadequate for animal and plant life. Its main feature is its ground ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salado River (Antofagasta, Chile)
Salado River is a river of Chile located in El Loa Province, Antofagasta Region which is in the northern part of the country. It is formed at the confluence of over 30 spring branches emerging from El Tatio area. Flowing briefly south, it turns west and passes through a canyon carved in volcanic rocks. In its middle course, the river receives the ''Toconce River'' (originated at the foot of Linzor volcano) from the north and the ''Caspana River'' from the south. In this area, a part of the flow of its affluents is diverted for providing water for domestic consumption in Antofagasta and Tocopilla, among other localities. After being joined by the two streams before mentioned, the Salado River enters in a floodplain area, which is used for pasturage by the inhabitants of the nearby localities, including Toconce, Caspana and Aiquina. Then, the Salado again flows through a narrow canyon, where is found the so-called ''Devil's Bridge'', a cut through rhyolite terrain of 5 m wide. Fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insolation
Solar irradiance is the power per unit area (surface power density) received from the Sun in the form of electromagnetic radiation in the wavelength range of the measuring instrument. Solar irradiance is measured in watts per square metre (W/m2) in SI units. Solar irradiance is often integrated over a given time period in order to report the radiant energy emitted into the surrounding environment (joule per square metre, J/m2) during that time period. This integrated solar irradiance is called solar irradiation, solar exposure, solar insolation, or insolation. Irradiance may be measured in space or at the Earth's surface after atmospheric absorption and scattering. Irradiance in space is a function of distance from the Sun, the solar cycle, and cross-cycle changes.Michael Boxwell, ''Solar Electricity Handbook: A Simple, Practical Guide to Solar Energy'' (2012), p. 41–42. Irradiance on the Earth's surface additionally depends on the tilt of the measuring surface, the height ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heinrich Event
A Heinrich event is a natural phenomenon in which large groups of icebergs break off from glaciers and traverse the North Atlantic. First described by marine geologist Hartmut Heinrich (Heinrich, H., 1988), they occurred during five of the last seven glacial periods over the past 640,000 years (Hodell, et al., 2008). Heinrich events are particularly well documented for the last glacial period but notably absent from the penultimate glaciation (Obrochta et al., 2014). The icebergs contained rock mass that had been eroded by the glaciers, and as they melted, this material was dropped to the sea floor as ice rafted debris (abbreviated to "IRD") forming deposits called Heinrich layers. The icebergs' melting caused vast quantities of fresh water to be added to the North Atlantic. Such inputs of cold and fresh water may well have altered the density-driven, thermohaline circulation patterns of the ocean, and often coincide with indications of global climate fluctuations. Various mech ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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