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53-560: Duckwater Valley is a valley in Nye County , Nevada . It starts south of the northern border of Nye County, and runs south for a distance of approximately 12 miles (19 km) to Railroad Valley . The Duckwater Valley is enclosed by the Pancake Range in the west and by the Duckwater Hills in the east. The Duckwater Creek crosses the valley. State Route 379 goes partially through

106-426: A balance of surface inflows, evaporation and seepage) are often called sinks. Endorheic lakes are typically located in the interior of a landmass, far from an ocean, and in areas of relatively low rainfall. Their watersheds are often confined by natural geologic land formations such as a mountain range, cutting off water egress to the ocean. The inland water flows into dry watersheds where the water evaporates, leaving

159-414: A broader floodplain may result. Deposition dominates over erosion. A typical river basin or drainage basin will incorporate each of these different types of valleys. Some sections of a stream or river valleys may have vertically incised their course to such an extent that the valley they occupy is best described as a gorge , ravine , or canyon . Rapid down-cutting may result from localized uplift of

212-527: A cirque glacier. During glacial periods, for example, the Pleistocene ice ages, it is in these locations that glaciers initially form and then, as the ice age proceeds, extend downhill through valleys that have previously been shaped by water rather than ice. Abrasion by rock material embedded within the moving glacial ice causes the widening and deepening of the valley to produce the characteristic U or trough shape with relatively steep, even vertical sides and

265-573: A high concentration of minerals and other inflow erosion products. Over time this input of erosion products can cause the endorheic lake to become relatively saline (a " salt lake "). Since the main outflow pathways of these lakes are chiefly through evaporation and seepage, endorheic lakes are usually more sensitive to environmental pollutant inputs than water bodies that have access to oceans, as pollution can be trapped in them and accumulate over time. Endorheic regions can occur in any climate but are most commonly found in desert locations. This reflects

318-788: A large portion of Europe drains to the endorheic Caspian Sea, Europe's wet climate means it contains relatively few terminal lakes itself: any such basin is likely to continue to fill until it reaches an overflow level connecting it with an outlet or erodes the barrier blocking its exit. There are some seemingly endorheic lakes, but they are cryptorheic, being drained either through manmade canals , via karstic phenomena, or other subsurface seepage. A few minor true endorheic lakes exist in Spain (e.g. Laguna de Gallocanta , Estany de Banyoles ), Italy , Cyprus ( Larnaca and Akrotiri salt lakes) and Greece . Many small lakes and ponds in North Dakota and

371-536: A limit of the erosion and deposition processes of nearby areas. Endorheic water bodies include the Caspian Sea , which is the world's largest inland body of water. The term endorheic derives from the French word endoréisme , which combines endo- ( Ancient Greek : ἔνδον éndon 'within') and ῥεῖν rheîn 'flow'. Endorheic lakes (terminal lakes) are bodies of water that do not flow into an ocean or

424-584: A narrow valley with steep sides. Gill is used to describe a ravine containing a mountain stream in Cumbria and the Pennines . The term combe (also encountered as coombe ) is widespread in southern England and describes a short valley set into a hillside. Other terms for small valleys such as hope, dean, slade, slack and bottom are commonly encountered in place-names in various parts of England but are no longer in general use as synonyms for valley . The term vale

477-519: A redistribution of water from these hydrologically landlocked basins such that endorheic water loss has contributed to sea level rise , and it is estimated that most of the terrestrial water lost ends up in the ocean. In regions such as Central Asia, where people depend on endorheic basins and other surface water sources to satisfy their water needs, human activity greatly impacts the availability of that water. Large endorheic regions in Africa are located in

530-432: A relatively flat bottom. Interlocking spurs associated with the development of river valleys are preferentially eroded to produce truncated spurs , typical of glaciated mountain landscapes. The upper end of the trough below the ice-contributing cirques may be a trough-end . Valley steps (or 'rock steps') can result from differing erosion rates due to both the nature of the bedrock (hardness and jointing for example) and

583-420: A sea. Most of the water that falls to Earth percolates into the oceans and the seas by way of a network of rivers, lakes, and wetlands . Analogous to endorheic lakes is the class of bodies of water located in closed watersheds (endorheic watersheds) where the local topography prevents the drainage of water into the oceans and the seas. These endorheic watersheds (containing water in rivers or lakes that form

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636-465: A slower rate than that of the main valley floor; thus the difference in the two valleys' depth increases over time. The tributary valley, composed of more resistant rock, then hangs over the main valley. Trough-shaped valleys also form in regions of heavy topographic denudation . By contrast with glacial U-shaped valleys, there is less downward and sideways erosion. The severe downslope denudation results in gently sloping valley sides; their transition to

689-427: A valley between its sides is referred to as the valley floor. The valley floor is typically formed by river sediments and may have fluvial terraces . The development of a river valley is affected by the character of the bedrock over which the river or stream flows, the elevational difference between its top and bottom, and indeed the climate. Typically the flow will increase downstream and the gradient will decrease. In

742-500: A variety of transitional forms between V-, U- and plain valleys can form. The floor or bottom of these valleys can be broad or narrow, but all valleys have a shoulder. The broader a mountain valley, the lower its shoulders are located in most cases. An important exception is canyons where the shoulder almost is near the top of the valley's slope. In the Alps – e.g. the Tyrolean Inn valley –

795-670: A watercourse only rarely. In areas of limestone bedrock , dry valleys may also result from drainage now taking place underground rather than at the surface. Rift valleys arise principally from earth movements , rather than erosion. Many different types of valleys are described by geographers, using terms that may be global in use or else applied only locally. Valleys may arise through several different processes. Most commonly, they arise from erosion over long periods by moving water and are known as river valleys. Typically small valleys containing streams feed into larger valleys which in turn feed into larger valleys again, eventually reaching

848-405: Is a tributary valley that is higher than the main valley. They are most commonly associated with U-shaped valleys, where a tributary glacier flows into a glacier of larger volume. The main glacier erodes a deep U-shaped valley with nearly vertical sides, while the tributary glacier, with a smaller volume of ice, makes a shallower U-shaped valley. Since the surfaces of the glaciers were originally at

901-403: Is one such case, with annual precipitation of 850 mm (33 in) and characterized by waterlogged soils that require draining. Endorheic regions tend to be far inland with their boundaries defined by mountains or other geological features that block their access to oceans. Since the inflowing water can evacuate only through seepage or evaporation, dried minerals or other products collect in

954-501: Is only 50 meters (160 ft) deep while the main fjord is around 1,300 meters (4,300 ft) at the same point. Glaciated terrain is not the only site of hanging streams and valleys. Hanging valleys are also simply the product of varying rates of erosion of the main valley and the tributary valleys. The varying rates of erosion are associated with the composition of the adjacent rocks in the different valley locations. The tributary valleys are eroded and deepened by glaciers or erosion at

1007-481: Is the word cwm borrowed from Welsh . The word dale occurs widely in place names in the north of England and, to a lesser extent, in southern Scotland. As a generic name for a type of valley, the term typically refers to a wide valley, though there are many much smaller stream valleys within the Yorkshire Dales which are named "(specific name) Dale". Clough is a word in common use in northern England for

1060-614: Is used in England and Wales to describe a wide river valley, usually with a particularly wide flood plain or flat valley bottom. In Southern England, vales commonly occur between the outcrops of different relatively erosion-resistant rock formations, where less resistant rock, often claystone has been eroded. An example is the Vale of White Horse in Oxfordshire. Some of the first human complex societies originated in river valleys, such as that of

1113-569: The Ely Record said the Duckwater Valley was "one of the most extensive ranching and farming sections in Eastern Nevada." The newspaper wrote that there were a number of ranches, one of which with 1,000 acres (400 ha) of land, of which 600 acres (240 ha) were in cultivation. Those ranches grew hay, grain, alfalfa , and potatoes, and were grazed by herds of cattle. The reservation of

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1166-610: The Bonneville flood . The Malheur / Harney lake system in Oregon is normally cut off from drainage to the ocean, but has an outflow channel to the Malheur River . This is presently dry, but may have flowed as recently as 1,000 years ago. Examples of relatively humid regions in endorheic basins often exist at high elevation. These regions tend to be marshy and are subject to substantial flooding in wet years. The area containing Mexico City

1219-564: The Duckwater Shoshone Tribe , that is situated entirely in the Duckwater Valley, has a surface area of over 3,850 acres (1,560 ha), and was officially created in 1940. The idea to establish a reservation had first been raised in 1937 by employees of the Florio Ranch, of which the owner wasn't able to pay the mortgage after he lost all his sheep in a blizzard. They figured they could sell the ranch together with some other ranches to

1272-649: The Latin terms for 'valley, 'gorge' and 'ditch' respectively. The German term ' rille ' or Latin term 'rima' (signifying 'cleft') is used for certain other elongate depressions on the Moon. See also: Endorheic basin An endorheic basin ( / ˌ ɛ n d oʊ ˈ r iː . ɪ k / EN -doh- REE -ik ; also endoreic basin and endorreic basin ) is a drainage basin that normally retains water and allows no outflow to other external bodies of water (e.g. rivers and oceans ); instead,

1325-496: The Nile , Tigris-Euphrates , Indus , Ganges , Yangtze , Yellow River , Mississippi , and arguably the Amazon . In prehistory , the rivers were used as a source of fresh water and food (fish and game), as well as a place to wash and a sewer. The proximity of water moderated temperature extremes and provided a source for irrigation , stimulating the development of agriculture . Most of

1378-906: The Sahara Desert , the Sahel , the Kalahari Desert , and the East African Rift : Endorheic lakes exist in Antarctica's McMurdo Dry Valleys , Victoria Land , the largest ice-free area. Much of Western and Central Asia is a giant endorheic region made up of a number of contiguous closed basins. The region contains several basins and terminal lakes, including: Other endorheic lakes and basins in Asia include: Australia , being very dry and having exceedingly low runoff ratios due to its ancient soils, has many endorheic drainages. The most important are: Though

1431-664: The first civilizations developed from these river valley communities. Siting of settlements within valleys is influenced by many factors, including the need to avoid flooding and the location of river crossing points. Numerous elongate depressions have been identified on the surface of Mars , Venus , the Moon , and other planets and their satellites and are known as valles (singular: 'vallis'). Deeper valleys with steeper sides (akin to canyons) on certain of these bodies are known as chasmata (singular: 'chasma'). Long narrow depressions are referred to as fossae (singular: 'fossa'). These are

1484-509: The Duckwater Valley as well. The only populated place in the valley is Duckwater . Part of the valley is occupied by the Duckwater Reservation . The valley had been inhabited for a long time by Native Americans , when the first white Americans settled in the Duckwater Valley in the 1860s after silver ore was discovered in nearby Hamilton . Agriculture arose in the valley, and for years hay, grain , vegetables, and fruit were grown for

1537-513: The Scandinavian ice sheet during the various ice ages advanced slightly uphill against the lie of the land. As a result, its meltwaters flowed parallel to the ice margin to reach the North Sea basin, forming huge, flat valleys known as Urstromtäler . Unlike the other forms of glacial valleys, these were formed by glacial meltwaters. Depending on the topography , the rock types , and the climate ,

1590-504: The actual valley bottom is unclear. Trough-shaped valleys occur mainly in periglacial regions and in tropical regions of variable wetness. Both climates are dominated by heavy denudation. Box valleys have wide, relatively level floors and steep sides. They are common in periglacial areas and occur in mid-latitudes, but also occur in tropical and arid regions. Rift valleys, such as the Albertine Rift and Gregory Rift are formed by

1643-493: The balance between tectonic subsidence and rates of evaporation and sedimentation. Where the basin floor is dropping more rapidly than water and sediments can accumulate, any lake in the basin will remain below the sill level (the level at which water can find a path out of the basin). Low rainfall or rapid evaporation in the watershed favor this case. In areas where rainfall is higher, riparian erosion will generally carve drainage channels (particularly in times of flood), or cause

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1696-456: The basin, eventually making the water saline and also making the basin vulnerable to pollution. Continents vary in their concentration of endorheic regions due to conditions of geography and climate. Australia has the highest percentage of endorheic regions at 21 per cent while North America has the least at five per cent. Approximately 18 per cent of the Earth's land drains to endorheic lakes or seas,

1749-564: The degree that a lake no longer forms. Even most permanent endorheic lakes change size and shape dramatically over time, often becoming much smaller or breaking into several smaller parts during the dry season. As humans have expanded into previously uninhabitable desert areas, the river systems that feed many endorheic lakes have been altered by the construction of dams and aqueducts. As a result, many endorheic lakes in developed or developing countries have contracted dramatically, resulting in increased salinity, higher concentrations of pollutants, and

1802-440: The disruption of ecosystems. Even within exorheic basins, there can be "non-contributing", low-lying areas that trap runoff and prevent it from contributing to flows downstream during years of average or below-average runoff. In flat river basins, non-contributing areas can be a large fraction of the river basin, e.g. Lake Winnipeg 's basin. A lake may be endorheic during dry years and can overflow its basin during wet years, e.g.,

1855-551: The expansion of the Earth 's crust due to tectonic activity beneath the Earth's surface. There are many terms used for different sorts of valleys. They include: Similar geographical features such as gullies , chines , and kloofs , are not usually referred to as valleys. The terms corrie , glen , and strath are all Anglicisations of Gaelic terms and are commonly encountered in place-names in Scotland and other areas where Gaelic

1908-443: The flow slower and both erosion and deposition may take place. More lateral erosion takes place in the middle section of a river's course, as strong currents on the outside of its curve erode the bank. Conversely, deposition may take place on the inside of curves where the current is much slacker, the process leading to the river assuming a meandering character. In the lower valley, gradients are lowest, meanders may be much broader and

1961-774: The former Tulare Lake . Because the Earth's climate has recently been through a warming and drying phase with the end of the Ice Ages, many endorheic areas such as Death Valley that are now dry deserts were large lakes relatively recently. During the last ice age, the Sahara may have contained lakes larger than any now existing. Climate change coupled with the mismanagement of water in these endorheic regions has led to devastating losses in ecosystem services and toxic surges of pollutants. The desiccation of saline lakes produces fine dust particles that impair agriculture productivity and harm human health. Anthropogenic activity has also caused

2014-719: The government for an Indian reservation. After the idea received the support of the Shoshone, the Bureau of Indian Affairs bought two ranches, and thus created the Indian reservation. At its creation, it had a size of 3,240 acres (1,310 ha), but the government has expanded it since by acquiring more ranch lands. Valley At lower latitudes and altitudes, these glacially formed valleys may have been created or enlarged during ice ages but now are ice-free and occupied by streams or rivers. In desert areas, valleys may be entirely dry or carry

2067-422: The inhabitants of Hamilton. Isaak "Ike" Irwin, who produced hay, was in 1868 the first person to settle in the present-day village Duckwater. When Hamilton was in decline, farmers in the Duckwater Valley started focussing on hay and grain, that they fed to their cattle. According to the 1881 book History of Nevada by Thompson and West, the valley consisted almost entirely of meadows, of which 800 acres (320 ha)

2120-427: The land surface or rejuvenation of the watercourse as a result for example of a reduction in the base level to which the river is eroded, e.g. lowered global sea level during an ice age . Such rejuvenation may also result in the production of river terraces . There are various forms of valleys associated with glaciation. True glacial valleys are those that have been cut by a glacier which may or may not still occupy

2173-422: The largest of these land areas being the interior of Asia. In deserts, water inflow is low and loss to solar evaporation high, drastically reducing the formation of complete drainage systems . In the extreme case, where there is no discernible drainage system, the basin is described as arheic . Closed water flow areas often lead to the concentration of salts and other minerals in the basin. Minerals leached from

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2226-463: The ocean or perhaps an internal drainage basin . In polar areas and at high altitudes, valleys may be eroded by glaciers ; these typically have a U-shaped profile in cross-section, in contrast to river valleys, which tend to have a V-shaped profile. Other valleys may arise principally through tectonic processes such as rifting . All three processes can contribute to the development of a valley over geological time. The flat (or relatively flat) portion of

2279-436: The power of the moving ice. In places, a rock basin may be excavated which may later be filled with water to form a ribbon lake or else by sediments. Such features are found in coastal areas as fjords . The shape of the valley which results from all of these influences may only become visible upon the recession of the glacier that forms it. A river or stream may remain in the valley; if it is smaller than one would expect given

2332-446: The same elevation , the shallower valley appears to be 'hanging' above the main valley. Often, waterfalls form at or near the outlet of the upper valley. Hanging valleys also occur in fjord systems underwater. The branches of Sognefjord are much shallower than the main fjord. The mouth of Fjærlandsfjord is about 400 meters (1,300 ft) deep while the main fjord nearby is 1,200 meters (3,900 ft) deep. The mouth of Ikjefjord

2385-543: The shoulders are quite low (100–200 meters above the bottom). Many villages are located here (esp. on the sunny side) because the climate is very mild: even in winter when the valley's floor is filled with fog, these villages are in sunshine . In some stress-tectonic regions of the Rocky Mountains or the Alps (e.g. Salzburg ), the side valleys are parallel to each other, and are hanging . Smaller streams flow into rivers as deep canyons or waterfalls . A hanging valley

2438-849: The size of its valley, it can be considered an example of a misfit stream . Other interesting glacially carved valleys include: A tunnel valley is a large, long, U-shaped valley originally cut under the glacial ice near the margin of continental ice sheets such as that now covering Antarctica and formerly covering portions of all continents during past glacial ages. Such valleys can be up to 100 km (62 mi) long, 4 km (2.5 mi) wide, and 400 m (1,300 ft) deep (its depth may vary along its length). Tunnel valleys were formed by subglacial water erosion . They once served as subglacial drainage pathways carrying large volumes of meltwater. Their cross-sections exhibit steep-sided flanks similar to fjord walls, and their flat bottoms are typical of subglacial glacial erosion. In northern Central Europe,

2491-599: The surrounding rocks are deposited in the basin, and left behind when the water evaporates. Thus endorheic basins often contain extensive salt pans (also called salt flats, salt lakes, alkali flats , dry lake beds, or playas). These areas tend to be large, flat hardened surfaces and are sometimes used for aviation runways , or land speed record attempts, because of their extensive areas of perfectly level terrain. Both permanent and seasonal endorheic lakes can form in endorheic basins. Some endorheic basins are essentially stable because climate change has reduced precipitation to

2544-407: The upper valley, the stream will most effectively erode its bed through corrasion to produce a steep-sided V-shaped valley. The presence of more resistant rock bands, of geological faults , fractures , and folds may determine the course of the stream and result in a twisting course with interlocking spurs . In the middle valley, as numerous streams have coalesced, the valley is typically wider,

2597-407: The valley at the present day. Such valleys may also be known as glacial troughs. They typically have a U-shaped cross-section and are characteristic landforms of mountain areas where glaciation has occurred or continues to take place. The uppermost part of a glacial valley frequently consists of one or more 'armchair-shaped' hollows, or ' cirques ', excavated by the rotational movement downslope of

2650-517: The water drainage flows into permanent and seasonal lakes and swamps that equilibrate through evaporation . Endorheic basins are also called closed basins , terminal basins , and internal drainage systems . Endorheic regions contrast with open lakes (exorheic regions), where surface waters eventually drain into the ocean. In general, water basins with subsurface outflows that lead to the ocean are not considered endorheic; but cryptorheic . Endorheic basins constitute local base levels , defining

2703-487: The water level in the terminal lake to rise until it finds an outlet, breaking the enclosed endorheic hydrological system's geographical barrier and opening it to the surrounding terrain. The Black Sea was likely such a lake, having once been an independent hydrological system before the Mediterranean Sea broke through the terrain separating the two. Lake Bonneville was another such lake, overflowing its basin in

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2756-416: Was occupied by agricultural lands. That land was used for growing grain and vegetables. Back then, some fruit plants had been planted recently. Thereafter, the livestock sector gradually grew in the Duckwater Valley, and it became the biggest in the valley. Around 1910, the farmers reduced the size of their cattle, because their rangelands were damaged by flocks of wild sheep in the winter season. In 1913,

2809-414: Was once widespread. Strath signifies a wide valley between hills, the floor of which is either level or slopes gently. A glen is a river valley which is steeper and narrower than a strath. A corrie is a basin-shaped hollow in a mountain. Each of these terms also occurs in parts of the world formerly colonized by Britain . Corrie is used more widely by geographers as a synonym for (glacial) cirque , as

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