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Qarhan Playa

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The Qarhan Playa or Salt Plain , also misleadingly described as Qarhan Lake , is a playa in the Golmud and Dulan counties of Haixi Prefecture , Qinghai , China . Formerly a single unitary lake, it is now an expansive salt flat divided into four greater sections ( Dabusun , Big / Small Bieletan , Suli , and N. / S. Huoluxun ) which contain a number of smaller salt lakes , the largest of which is Dabusun Lake. The area is heavily exploited for its valuable salt, mineral, and rare earth reserves but parts are also protected as a national park and contribute to regional tourism.

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65-678: Qarhan is the GNC romanization of the area's Mongolian name, originally derived from the word for "white" (Modern Mongolian : цагаан , tsagaan , or ᠴᠠᠭᠠᠨ , čaɣan ). Cha'erhan is the pinyin romanization of the Mandarin pronunciation of 察爾汗 , a modification of the original transcription into Chinese characters of the same name; it is also sometimes clipped into Charhan in English sources. The Chinese name, which does not distinguish between actual salt lakes and playas , also causes

130-409: A body of water from 2 hectares (5 acres) to 8 hectares (20 acres). Pioneering animal ecologist Charles Elton regarded lakes as waterbodies of 40 hectares (99 acres) or more. The term lake is also used to describe a feature such as Lake Eyre , which is a dry basin most of the time but may become filled under seasonal conditions of heavy rainfall. In common usage, many lakes bear names ending with

195-500: A comprehensive analysis of the origin of lakes and proposed what is a widely accepted classification of lakes according to their origin. This classification recognizes 11 major lake types that are divided into 76 subtypes. The 11 major lake types are: Tectonic lakes are lakes formed by the deformation and resulting lateral and vertical movements of the Earth's crust. These movements include faulting, tilting, folding, and warping. Some of

260-402: A form of organic lake. They form where a buildup of partly decomposed plant material in a wet environment leaves the vegetated surface below the water table for a sustained period of time. They are often low in nutrients and mildly acidic, with bottom waters low in dissolved oxygen. Artificial lakes or anthropogenic lakes are large waterbodies created by human activity . They can be formed by

325-449: A further 50,000–200,000 t (55,000–220,000 short tons) a year. During a 2016 inspection tour, Chinese Communist Party general secretary Xi Jinping praised the importance of the factories and their workers to the entire country but emphasized the need for Qarhan's development to be environmentally responsible . As part of a national program to increase the use of electric cars , automobile companies like BYD have since moved to

390-538: A higher perimeter to area ratio than other lake types. These form where sediment from a tributary blocks the main river. These form where sediment from the main river blocks a tributary, usually in the form of a levee . Lakes formed by other processes responsible for floodplain basin creation. During high floods they are flushed with river water. There are four types: 1. Confluent floodplain lake, 2. Contrafluent-confluent floodplain lake, 3. Contrafluent floodplain lake, 4. Profundal floodplain lake. A solution lake

455-510: A hypolimnion; accordingly, very shallow lakes are excluded from this classification system. Based upon their thermal stratification, lakes are classified as either holomictic , with a uniform temperature and density from top to bottom at a given time of year, or meromictic , with layers of water of different temperature and density that do not intermix. The deepest layer of water in a meromictic lake does not contain any dissolved oxygen so there are no living aerobic organisms . Consequently,

520-428: A lake consists of a large area of standing water that occupies an extensive closed depression in limestone, it is also called a karst lake . Smaller solution lakes that consist of a body of standing water in a closed depression within a karst region are known as karst ponds. Limestone caves often contain pools of standing water, which are known as underground lakes . Classic examples of solution lakes are abundant in

585-470: A large number of studies agree that small ponds are much more abundant than large lakes. For example, one widely cited study estimated that Earth has 304 million lakes and ponds, and that 91% of these are 1 hectare (2.5 acres) or less in area. Despite the overwhelming abundance of ponds, almost all of Earth's lake water is found in fewer than 100 large lakes; this is because lake volume scales superlinearly with lake area. Extraterrestrial lakes exist on

650-711: A national mining park on 1 August 2008. Sections of the G3011 Liuge Expressway and the Qingzang Railway run over the playa's salt flats. SASM Too Many Requests If you report this error to the Wikimedia System Administrators, please include the details below. Request from 172.68.168.133 via cp1102 cp1102, Varnish XID 551453252 Upstream caches: cp1102 int Error: 429, Too Many Requests at Thu, 28 Nov 2024 05:33:42 GMT Ephemeral lake A lake

715-489: A natural outflow and lose water solely by evaporation or underground seepage, or both. These are termed endorheic lakes. Many lakes are artificial and are constructed for hydroelectric power generation, aesthetic purposes, recreational purposes, industrial use, agricultural use, or domestic water supply . The number of lakes on Earth is undetermined because most lakes and ponds are very small and do not appear on maps or satellite imagery . Despite this uncertainty,

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780-403: A result of meandering. The slow-moving river forms a sinuous shape as the outer side of bends are eroded away more rapidly than the inner side. Eventually a horseshoe bend is formed and the river cuts through the narrow neck. This new passage then forms the main passage for the river and the ends of the bend become silted up, thus forming a bow-shaped lake. Their crescent shape gives oxbow lakes

845-535: A result of the 1959 Hebgen Lake earthquake . Most landslide lakes disappear in the first few months after formation, but a landslide dam can burst suddenly at a later stage and threaten the population downstream when the lake water drains out. In 1911, an earthquake triggered a landslide that blocked a deep valley in the Pamir Mountains region of Tajikistan , forming the Sarez Lake . The Usoi Dam at

910-527: A stroll on 2 October 1957. The next year, an exploratory well discovered the Yanhu Gas Field north of Dabusun Lake. Over the next decade, more detailed surveying and prospecting were undertaken while China continued to depend on Canadian imports for its potash. Commercial exploitation of the basin's own potash began in 1989, following the expansion of the PRC's Opening Up and Reform Policy . The opening of

975-422: A variation in density because of thermal gradients. Stratification can also result from a density variation caused by gradients in salinity. In this case, the hypolimnion and epilimnion are separated not by a thermocline but by a halocline , which is sometimes referred to as a chemocline . Lakes are informally classified and named according to the seasonal variation in their lake level and volume. Some of

1040-454: A whole holds 83% of the country's known lithium reserves, with some areas having concentrations of 330 ppm . Paleoclimatologists believe that the playa's basin was created by tectonic activity during the Mesozoic . Between 770,000 and 30,000 years ago the basin constituted an enormous lake, which alternated nine times between being a fresh- and saltwater lake. Pollen studies suggest that

1105-443: Is sag ponds . Volcanic lakes are lakes that occupy either local depressions, e.g. craters and maars , or larger basins, e.g. calderas , created by volcanism . Crater lakes are formed in volcanic craters and calderas, which fill up with precipitation more rapidly than they empty via either evaporation, groundwater discharge, or a combination of both. Sometimes the latter are called caldera lakes, although often no distinction

1170-403: Is a lake occupying a basin formed by surface dissolution of bedrock. In areas underlain by soluble bedrock, its solution by precipitation and percolating water commonly produce cavities. These cavities frequently collapse to form sinkholes that form part of the local karst topography . Where groundwater lies near the grounds surface, a sinkhole will be filled water as a solution lake. If such

1235-424: Is an often naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land . Lakes lie completely on land and are separate from the ocean , although they may be connected with the ocean by rivers . Lakes, as with other bodies of water , are part of the water cycle , the processes by which water moves around

1300-468: Is dammed behind an ice shelf that is attached to the coastline. They are mostly found in Antarctica. Fluvial (or riverine) lakes are lakes produced by running water. These lakes include plunge pool lakes , fluviatile dams and meander lakes. The most common type of fluvial lake is a crescent-shaped lake called an oxbow lake due to the distinctive curved shape. They can form in river valleys as

1365-452: Is made. An example is Crater Lake in Oregon , in the caldera of Mount Mazama . The caldera was created in a massive volcanic eruption that led to the subsidence of Mount Mazama around 4860 BCE. Other volcanic lakes are created when either rivers or streams are dammed by lava flows or volcanic lahars . The basin which is now Malheur Lake , Oregon was created when a lava flow dammed

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1430-630: Is sometimes known as the Sanhu ("Three Lakes"), after the two Taijinar lakes, Suli Lake , and Dabusun . Qarhan is part of the larger Qaidam Basin , lying between the Kunlun Mountains to the south, the Altun to the west, and the Qilian to the north. Qarhan's lakes lie between 2,675–2,680 m (8,780–8,790 ft) above sea level , with Dabusun and North Hulsan being the lowest and Xiezuo being

1495-429: Is unknown but is estimated to be at least 2 million. Finland has 168,000 lakes of 500 square metres (5,400 sq ft) in area, or larger, of which 57,000 are large (10,000 square metres (110,000 sq ft) or larger). Most lakes have at least one natural outflow in the form of a river or stream , which maintain a lake's average level by allowing the drainage of excess water. Some lakes do not have

1560-759: The Malheur River . Among all lake types, volcanic crater lakes most closely approximate a circular shape. Glacial lakes are lakes created by the direct action of glaciers and continental ice sheets. A wide variety of glacial processes create enclosed basins. As a result, there are a wide variety of different types of glacial lakes and it is often difficult to define clear-cut distinctions between different types of glacial lakes and lakes influenced by other activities. The general types of glacial lakes that have been recognized are lakes in direct contact with ice, glacially carved rock basins and depressions, morainic and outwash lakes, and glacial drift basins. Glacial lakes are

1625-499: The Proto-Indo-European root * leǵ- ('to leak, drain'). Cognates include Dutch laak ('lake, pond, ditch'), Middle Low German lāke ('water pooled in a riverbed, puddle') as in: de:Wolfslake , de:Butterlake , German Lache ('pool, puddle'), and Icelandic lækur ('slow flowing stream'). Also related are the English words leak and leach . There is considerable uncertainty about defining

1690-399: The density of water varies with temperature, with a maximum at +4 degrees Celsius, thermal stratification is an important physical characteristic of a lake that controls the fauna and flora , sedimentation, chemistry, and other aspects of individual lakes. First, the colder, denser water typically forms a layer near the bottom, which is called the hypolimnion . Second, normally overlying

1755-597: The Earth by extraterrestrial objects (either meteorites or asteroids ). Examples of meteorite lakes are Lonar Lake in India, Lake El'gygytgyn in northeast Siberia, and the Pingualuit crater lake in Quebec, Canada. As in the cases of El'gygytgyn and Pingualuit, meteorite lakes can contain unique and scientifically valuable sedimentary deposits associated with long records of paleoclimatic changes. In addition to

1820-420: The Earth. Most lakes are freshwater and account for almost all the world's surface freshwater, but some are salt lakes with salinities even higher than that of seawater . Lakes vary significantly in surface area and volume of water. Lakes are typically larger and deeper than ponds , which are also water-filled basins on land, although there are no official definitions or scientific criteria distinguishing

1885-571: The Lusatian Lake District, Germany. In India, Sudarshana Lake is a historical artificial lake located in the semi-arid region of Girnar, Gujarat, originally constructed during the reign of Chandragupta Maurya. See: List of notable artificial lakes in the United States Meteorite lakes, also known as crater lakes (not to be confused with volcanic crater lakes ), are created by catastrophic impacts with

1950-606: The Qarhan Playa is solid halite underlain by a layer of brine to about 1.3 m (4 ft 3 in) under the soil, and it holds enormous reserves of salt , with solid layers extending between 2–20 m (6 ft 7 in – 65 ft 7 in). The 50 billion metric tons (55 billion short tons) are estimated sufficient to meet present world demand for 1,000 years. The area around Dabusun Lake has halite to depths of at least 40 m (130 ft), although with alternating layers of mud in places. The salinity of

2015-496: The Qinghai Potash Fertilizer Factory increased China's production of potassium chloride sixfold, from less than 40,000 t (44,000 short tons) a year at Haixi and Tanggu to just under 240,000 t (260,000 short tons) a year. As of 2010, production was over 1 million metric tons (1.1 million short tons) a year at the main site, with smaller operations around the playa each producing

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2080-430: The area of the lake bed which now underlies Dabusun was raised around 700 m (2,300 ft) in just the last 500,000 years. Tectonic activity also shifted the lake's tributaries and basins, although it remained with the present-day playa during this period. At around 30,000 years ago, this great freshwater lake spread over at least 25,000 km (9,700 sq mi) with a surface 50–60 m (160–200 ft) above

2145-404: The area, opened factories, and signed contracts with local mining companies to exploit the area's lithium supplies. Infrastructure has been improved, including an overhaul of Golmud Airport . The fertilizer factory is now open to the public for free tours, and its parent company maintains a nearby museum covering the geology of the playa and hosting various salt sculptures. The area was designated

2210-866: The base of the valley has remained in place for more than 100 years but the terrain below the lake is in danger of a catastrophic flood if the dam were to fail during a future earthquake. Tal-y-llyn Lake in north Wales is a landslide lake dating back to the last glaciation in Wales some 20000 years ago. Aeolian lakes are produced by wind action . These lakes are found mainly in arid environments, although some aeolian lakes are relict landforms indicative of arid paleoclimates . Aeolian lakes consist of lake basins dammed by wind-blown sand; interdunal lakes that lie between well-oriented sand dunes ; and deflation basins formed by wind action under previously arid paleoenvironments. Moses Lake in Washington , United States,

2275-594: The basins of the salt flat's four main sections—Bieletan, Dabusun, Qarhan, and Huoluxun—with about ten large but shallow lakes usually collectively occupying an area of about 460 km (180 sq mi): Suli Lake in the west, fed from the west by the Urt Moron ; the Little and Big Biele Lakes beside it, fed from the south by the Tuolahai and Qingshui Rivers ; West Dabusun and Dabusun Lake (the largest), in

2340-574: The center, fed from the south by the Golmud River ; Dongling Lake to their northwest; Xiezuo and Tuanjie Lakes to their east, fed respectively by the intermittent Quanji and Shougong Rivers ; and North and South Hulsan Lakes at the east end of the playa, fed from the east by the Qaidam , Nuomuhong , and Suolinguole Rivers . All of these are usually less than 1 m (3 ft 3 in) deep. There are also some ephemeral lakes . Most of

2405-915: The courses of mature rivers, where a river channel has widened over a basin formed by eroded floodplains and wetlands . Some lakes are found in caverns underground . Some parts of the world have many lakes formed by the chaotic drainage patterns left over from the last ice age . All lakes are temporary over long periods of time , as they will slowly fill in with sediments or spill out of the basin containing them. Artificially controlled lakes are known as reservoirs , and are usually constructed for industrial or agricultural use, for hydroelectric power generation, for supplying domestic drinking water , for ecological or recreational purposes, or for other human activities. The word lake comes from Middle English lake ('lake, pond, waterway'), from Old English lacu ('pond, pool, stream'), from Proto-Germanic * lakō ('pond, ditch, slow moving stream'), from

2470-518: The creation of lakes by the disruption of preexisting drainage networks, it also creates within arid regions endorheic basins that contain salt lakes (also called saline lakes). They form where there is no natural outlet, a high evaporation rate and the drainage surface of the water table has a higher-than-normal salt content. Examples of these salt lakes include Great Salt Lake and the Dead Sea . Another type of tectonic lake caused by faulting

2535-622: The difference between lakes and ponds , and neither term has an internationally accepted definition across scientific disciplines or political boundaries. For example, limnologists have defined lakes as water bodies that are simply a larger version of a pond, which can have wave action on the shoreline or where wind-induced turbulence plays a major role in mixing the water column. None of these definitions completely excludes ponds and all are difficult to measure. For this reason, simple size-based definitions are increasingly used to separate ponds and lakes. Definitions for lake range in minimum sizes for

2600-569: The district remained largely unpopulated, as the salt deposits made it difficult for the nomads of northwestern China to use the area for their herds. National geological expeditions began investigating Qinghai in the 1950s, shortly after the establishment of the People's Republic of China . The major expedition to the Qarhan Playa was undertaken in 1955–6, but the area's important carnallite (and thus potassium ) reserves were discovered accidentally by geologists Zheng Mianping and Liu Dagang during

2665-536: The exception of criterion 3, the others have been accepted or elaborated upon by other hydrology publications. The majority of lakes on Earth are freshwater , and most lie in the Northern Hemisphere at higher latitudes . Canada , with a deranged drainage system , has an estimated 31,752 lakes larger than 3 square kilometres (1.2 sq mi) in surface area. The total number of lakes in Canada

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2730-610: The highest. The effect of elevation is such that despite lying on the same latitude as Greece , Algeria , and Virginia in the United States , Qarhan has a mean annual temperature of 0.1 °C (32.2 °F). The mean air speed is 4.3 m/s (9.6 mph), and the mean relative humidity is 27.7%. In the playa's hyperarid climate, there is generally only 28–40 mm (1–2 in) of annual rainfall but 3,000–3,564 mm (118.1–140.3 in) of annual evaporation. Despite this, meltwater rivers and mineral springs fill

2795-422: The hypolimnion is a transition zone known as the metalimnion . Finally, overlying the metalimnion is a surface layer of warmer water with a lower density, called the epilimnion . This typical stratification sequence can vary widely, depending on the specific lake or the time of year, or a combination of both. The classification of lakes by thermal stratification presupposes lakes with sufficient depth to form

2860-907: The intentional damming of rivers and streams, rerouting of water to inundate a previously dry basin , or the deliberate filling of abandoned excavation pits by either precipitation runoff , ground water , or a combination of both. Artificial lakes may be used as storage reservoirs that provide drinking water for nearby settlements , to generate hydroelectricity , for flood management , for supplying agriculture or aquaculture , or to provide an aquatic sanctuary for parks and nature reserves . The Upper Silesian region of southern Poland contains an anthropogenic lake district consisting of more than 4,000 water bodies created by human activity. The diverse origins of these lakes include: reservoirs retained by dams, flooded mines, water bodies formed in subsidence basins and hollows, levee ponds, and residual water bodies following river regulation. Same for

2925-471: The karst regions at the Dalmatian coast of Croatia and within large parts of Florida . A landslide lake is created by the blockage of a river valley by either mudflows , rockslides , or screes . Such lakes are most common in mountainous regions. Although landslide lakes may be large and quite deep, they are typically short-lived. An example of a landslide lake is Quake Lake , which formed as

2990-657: The largest lakes on Earth are rift lakes occupying rift valleys, e.g. Central African Rift lakes and Lake Baikal . Other well-known tectonic lakes, Caspian Sea , the Sea of Aral , and other lakes from the Pontocaspian occupy basins that have been separated from the sea by the tectonic uplift of the sea floor above the ocean level. Often, the tectonic action of crustal extension has created an alternating series of parallel grabens and horsts that form elongate basins alternating with mountain ranges. Not only does this promote

3055-528: The layers of sediment at the bottom of a meromictic lake remain relatively undisturbed, which allows for the development of lacustrine deposits . In a holomictic lake, the uniformity of temperature and density allows the lake waters to completely mix. Based upon thermal stratification and frequency of turnover, holomictic lakes are divided into amictic lakes , cold monomictic lakes , dimictic lakes , warm monomictic lakes, polymictic lakes , and oligomictic lakes. Lake stratification does not always result from

3120-560: The level of a lake are controlled by the difference between the input and output compared to the total volume of the lake. Significant input sources are precipitation onto the lake, runoff carried by streams and channels from the lake's catchment area, groundwater channels and aquifers, and artificial sources from outside the catchment area. Output sources are evaporation from the lake, surface and groundwater flows, and any extraction of lake water by humans. As climate conditions and human water requirements vary, these will create fluctuations in

3185-481: The mainland; lakes cut off from larger lakes by a bar; or lakes divided by the meeting of two spits. Organic lakes are lakes created by the actions of plants and animals. On the whole they are relatively rare in occurrence and quite small in size. In addition, they typically have ephemeral features relative to the other types of lakes. The basins in which organic lakes occur are associated with beaver dams, coral lakes, or dams formed by vegetation. Peat lakes are

3250-424: The mode of origin, lakes have been named and classified according to various other important factors such as thermal stratification , oxygen saturation, seasonal variations in lake volume and water level, salinity of the water mass, relative seasonal permanence, degree of outflow, and so on. The names used by the lay public and in the scientific community for different types of lakes are often informally derived from

3315-485: The moon Titan , which orbits the planet Saturn . The shape of lakes on Titan is very similar to those on Earth. Lakes were formerly present on the surface of Mars, but are now dry lake beds . In 1957, G. Evelyn Hutchinson published a monograph titled A Treatise on Limnology , which is regarded as a landmark discussion and classification of all major lake types, their origin, morphometric characteristics, and distribution. Hutchinson presented in his publication

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3380-415: The morphology of the lakes' physical characteristics or other factors. Also, different cultures and regions of the world have their own popular nomenclature. One important method of lake classification is on the basis of thermal stratification, which has a major influence on the animal and plant life inhabiting a lake, and the fate and distribution of dissolved and suspended material in the lake. For example,

3445-406: The most numerous lakes in the world. Most lakes in northern Europe and North America have been either influenced or created by the latest, but not last, glaciation, to have covered the region. Glacial lakes include proglacial lakes , subglacial lakes , finger lakes , and epishelf lakes. Epishelf lakes are highly stratified lakes in which a layer of freshwater, derived from ice and snow melt,

3510-791: The names include: Lakes may be informally classified and named according to the general chemistry of their water mass. Using this classification method, the lake types include: A paleolake (also palaeolake ) is a lake that existed in the past when hydrological conditions were different. Quaternary paleolakes can often be identified on the basis of relict lacustrine landforms, such as relict lake plains and coastal landforms that form recognizable relict shorelines called paleoshorelines . Paleolakes can also be recognized by characteristic sedimentary deposits that accumulated in them and any fossils that might be contained in these sediments. The paleoshorelines and sedimentary deposits of paleolakes provide evidence for prehistoric hydrological changes during

3575-562: The organic-rich deposits of pre-Quaternary paleolakes are important either for the thick deposits of oil shale and shale gas contained in them, or as source rocks of petroleum and natural gas . Although of significantly less economic importance, strata deposited along the shore of paleolakes sometimes contain coal seams . Lakes have numerous features in addition to lake type, such as drainage basin (also known as catchment area), inflow and outflow, nutrient content, dissolved oxygen , pollutants , pH , and sedimentation . Changes in

3640-751: The playa to be called a "lake" or even "the largest salt lake in China" in less careful English sources. The Qarhan Playa covers an area of 5,856 km (2,261 sq mi), stretching over 160 km (100 mi) east to west and usually between 20–40 km (12–25 mi) north to south. The southwest lies in Golmud and the northeast in Dulan County , both in Haixi Prefecture , Qinghai , China . The roughly 60,000 km (23,000 sq mi) area of Qarhan inclusive of Taijinar to its west

3705-473: The playa's lakes varies between 164.81 and 359.50 g/L (1.3–3 lb/gal); their pH values are between 5.4 and 7.85. Other minerals include potash , carnallite ( potassium magnesium chloride ), calcium chloride , magnesium , lithium , boron , iodine , and sylvite . The basin is one of China's richest sources for potassium , with an estimated 360 million metric tons (400 million short tons) of potassium oxide . Its reserves are also important as

3770-404: The present levels of its successors, making it one of the largest lakes in the world . It was cut off and became saline again around 30,000 years ago and began precipitating salts about 25,000 years ago. It has been shrinking in size by evaporation for most of that time, eventually separating into the current separate lakes. Until the recent commercial exploitation of the salts and other minerals,

3835-622: The streams contributing to these lakes flow north into the playa from the Kunlun and its foothills. The Golmud River is the main contributor, providing a mean annual influx of 19.2 trillion L (5.07 trillion gal) of water. There is also contribution of about 1% from mineral springs , especially on the north end of the playa, which play an important role in the chemical composition of the sediment. The local flora consists of sparse forbs (particularly members of Chenopodioideae ) and shrubs , especially members of Ephedra and Tamarix . Most of

3900-404: The thermal stratification, as well as the degree and frequency of mixing, has a strong control over the distribution of oxygen within the lake. Professor F.-A. Forel , also referred to as the "Father of limnology", was the first scientist to classify lakes according to their thermal stratification. His system of classification was later modified and improved upon by Hutchinson and Löffler. As

3965-456: The times that they existed. There are two types of paleolake: Paleolakes are of scientific and economic importance. For example, Quaternary paleolakes in semidesert basins are important for two reasons: they played an extremely significant, if transient, role in shaping the floors and piedmonts of many basins; and their sediments contain enormous quantities of geologic and paleontologic information concerning past environments. In addition,

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4030-641: The two. Lakes are also distinct from lagoons , which are generally shallow tidal pools dammed by sandbars or other material at coastal regions of oceans or large lakes. Most lakes are fed by springs , and both fed and drained by creeks and rivers , but some lakes are endorheic without any outflow, while volcanic lakes are filled directly by precipitation runoffs and do not have any inflow streams. Natural lakes are generally found in mountainous areas (i.e. alpine lakes ), dormant volcanic craters , rift zones and areas with ongoing glaciation . Other lakes are found in depressed landforms or along

4095-467: The word pond , and a lesser number of names ending with lake are, in quasi-technical fact, ponds. One textbook illustrates this point with the following: "In Newfoundland, for example, almost every lake is called a pond, whereas in Wisconsin, almost every pond is called a lake." One hydrology book proposes to define the term "lake" as a body of water with the following five characteristics: With

4160-498: The world's largest present-day accumulation of potassium-rich salt in the world, which helped scientists better understand the chemical and evaporation pathways involved in the creation of natural potash and disprove previous suppositions that it only formed in marine environments. The Bieletan subbasin in the west is the richest source of brine lithium in China, with an estimated reserve of 7.74 million metric tons (8.53 million short tons) of lithium chloride . The Sanhu as

4225-617: Was originally a shallow natural lake and an example of a lake basin dammed by wind-blown sand. China's Badain Jaran Desert is a unique landscape of megadunes and elongated interdunal aeolian lakes, particularly concentrated in the southeastern margin of the desert. Shoreline lakes are generally lakes created by blockage of estuaries or by the uneven accretion of beach ridges by longshore and other currents. They include maritime coastal lakes, ordinarily in drowned estuaries; lakes enclosed by two tombolos or spits connecting an island to

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