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37-537: Over time, in regions where a lake once existed, as water drains or evaporates from the lake, the deposited sediments are left behind, resulting in a level plain of land where the lake once existed. The soil of the plain may constitute fertile and productive farmland due to the previous accumulation of lacustrine sediments; in other cases, it may become a wetland or a desert . Lacustrine plains are plains formed when lakes filled with sediments are drained. There are several reasons why drainage might occur, but in all cases

74-578: A salt flat . If its basin is primarily salt , then a dry lake bed is called a salt pan , pan , or salt flat (the latter being a remnant of a salt lake ). Hardpan is the dry terminus of an internally drained basin in a dry climate, a designation typically used in the Great Basin of the western United States. Another term for dry lake bed is playa . The Spanish word playa ( pronounced [ˈplaʝa] ) literally means "beach". Dry lakes are known by this name in some parts of Mexico and

111-455: A pass (sometimes termed a gap ). Coastal plains mostly rise from sea level until they run into elevated features such as mountains or plateaus. Plains can be formed from flowing lava ; from deposition of sediment by water, ice, or wind; or formed by erosion by the agents from hills or mountains. Biomes on plains include grassland ( temperate or subtropical ), steppe ( semi-arid ), savannah ( tropical ) or tundra ( polar ). In

148-673: A dry lake bed for years until conditions are optimum for hatching. Lepidium davisii is another rare species, a perennial plant whose habitat is restricted to playas in southern Idaho and northern Nevada. Far from major rivers or lakes, playas are often the only water available to wildlife in the desert. Antelope and other wildlife gather there after rainstorms to drink. Threats to dry lakes include pollution from concentrated animal feeding operations such as cattle feedlots and dairies. Results are erosion; fertilizer, pesticide and sediment runoff from farms; and overgrazing . A non-native shrub that has been used for rangeland restoration in

185-538: A few instances, deserts and rainforests may also be considered plains. Plains in many areas are important for agriculture because where the soils were deposited as sediments they may be deep and fertile , and the flatness facilitates mechanization of crop production; or because they support grasslands which provide good grazing for livestock . The types of depositional plains include: Erosional plains have been leveled by various agents of denudation such as running water, rivers, wind and glacier which wear out

222-587: A flat bed of clay, generally encrusted with precipitated salts. These evaporite minerals are a concentration of weathering products such as sodium carbonate, borax, and other salts. In deserts, a dry lake may be found in an area ringed by bajadas . Dry lakes are typically formed in semi- arid to arid regions of the world. The largest concentration of dry lakes (nearly 22,000) is in the southern High Plains of Texas and eastern New Mexico . Most dry lakes are small. However, Salar de Uyuni in Bolivia , near Potosí ,

259-402: A number of rare species that occur nowhere else but in the inhospitable environment of seasonally flooded playas. A new species of giant fairy shrimp was found in 2006. Although a large predatory species, it evaded detection because of the murkiness of the playa's water caused by winds and a fine clay load. This shrimp species is able to regenerate using tiny undetectable cysts that can remain in

296-400: A perfect coincidence of events. First, the playa has to fill with water, which must be deep enough to form floating ice during winter, but still shallow enough that the rocks are exposed. When the temperature drops at night, this pond freezes into thin sheets of "windowpane" ice, which then must be thick enough to maintain strength, but thin enough to move freely. Finally, when the sun comes out,

333-614: A playa in the Black Rock Desert in western Nevada every year. Fangfang Yao et al (2023), at the University of Virginia reported that more than half of the world's large lakes are drying up. They assessed almost 2,000 large lakes using satellite measurements combined with climate and hydrological models. They found that unsustainable human use, changes in rainfall and run-off, sedimentation, and rising temperatures have driven lake levels down globally, with 53% of lakes showing

370-611: A redirection of the rivers, causing the Paleo-lake Obweruka to break into smaller regional lakes and the drainage system to change. Tectonics-induced lacustrine plain formation can also be found at the Congo Lake Plain and the Lake Plain of South Sudan. While differential uplift can certainly create inland basins and lakes, many inland lakes are created due to a period of heavy and consistent rainfall that

407-478: A variety of places. For instance, Lake Agassiz -Ojibway Basin in northwestern Quebec is a good example of lacustrine plain formation caused by the ice readvance and drainage of Lake Ojibway . By analyzing the varve sequences and dividing them into the Matagami section and La Reine section, researchers were able to determine the time of occurrence for a major ice readvance event in the area and two drainage events in

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444-584: Is Lake Eyre in South Australia. The Lake Eyre North basin formed due to tectonic subsidence, and repeating glacial cycles and climatic cycles led to wet and dry cycles in the lake where the state of the lake changed drastically. Lake Eyre is currently a playa , indicating that it is in a relatively arid episode. However, it was much wetter when it was in flood-dominated episodes, and it held more water than its current ephemeral state. The Chad Basin Plain

481-519: Is a drainage system formed by mantle plumes activity induced tectonic uplift, forming the Rwenzori and Virunga Mountains. This uplift led to a segmentation of the west East African Rift System and led to the difference in flowing directions of the rivers in the northwestern Main Ethiopian Rift and the eastern and western East African Rift System . The regional tectonics therefore contributed to

518-551: Is also a good example of inland lacustrine plain formation. By conducting facies analysis, researchers are able to determine four lithofacies associations for the Chad Basin, and thus the sequences of the Chad Basin's formation. Those lithofacies with little plant debris indicate a period of aridity and represent the last sequence of Chad formation where a lacustrine plain existed. Other examples of inland lake creation, drainage, and lake plain formation can be found at plains near

555-428: Is formed when water from rain or other sources, like intersection with a water table, flows into a dry depression in the landscape, creating a pond or lake. If the total annual evaporation rate exceeds the total annual inflow, the depression will eventually become dry again, forming a dry lake. Salts originally dissolved in the water precipitate out and are left behind, gradually building up over time. A dry lake appears as

592-621: Is very little water, dunes can form. The Racetrack Playa , located in Death Valley, California , features a geological phenomenon known as " sailing stones " that leave linear "racetrack" imprints as they slowly move across the surface without human or animal intervention. These rocks have been recently filmed in motion by the Scripps Institution of Oceanography at the University of California, San Diego and are due to

629-656: The Caspian Sea and the Lake Bonneville Plain. The Great Plains in North America are examples of the agricultural values of lacustrine plains. The flat lake plain where Lake Agassiz once existed now serves as a cropland for sugar beets and potatoes. Beneficial to the growth of the crops, the soils of the lacustrine plains in the Great Lakes region are fertile due to prior sedimentation, and

666-613: The Chrissiesmeer area, to the extensive pans of the Northern Cape province. Terms used in Australia include salt pans (where evaporite minerals are present) and clay pans . In Arabic, a salt flat is called a sabkha (also spelled sabkhah , subkha or sebkha ) or shott ( chott ). In Central Asia, a similar "cracked mud" salt flat is known as a takyr . In Iran salt flats are called kavir . A dry lake

703-451: The Earth's surface. Dry lake A dry lake bed , also known as a playa ( / ˈ p l aɪ - ə / ), is a basin or depression that formerly contained a standing surface water body, which disappears when evaporation processes exceed recharge. If the floor of a dry lake is covered by deposits of alkaline compounds, it is known as an alkali flat. If covered with salt, it is known as

740-472: The base of mountains , as coastal plains , and as plateaus or uplands . Plains are one of the major landforms on earth, where they are present on all continents, and cover more than one-third of the world's land area. In a valley, a plain is enclosed on two sides, but in other cases a plain may be delineated by a complete or partial ring of hills, by mountains, or by cliffs . Where a geological region contains more than one plain, they may be connected by

777-473: The conditions in which they form. Lake formations depending on the existence of active glaciers are different from those depending on the proximity of the lake to glaciers and those depending on glacier retreats. Regardless of the difference in those glacial lakes' formation conditions, lakes that are trapped inside ice walls drain after the ice walls melt, and the sediments in the lakes form glaciolacustrine plains. Glaciolacustrine plain formations can be found in

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814-544: The drainage of glacial lakes are called glaciolacustrine plains, which differ from those resulting from differential uplifts and those from the creation of inland lakes. Glaciolacustrine plains form when the lakes in the continental ice sheets drain and leave the rocky debris within behind. The most recent ice age, the Wisconsin, was a drive for glacial lake formation and the glaciolacustrine plain formation that followed. Glacial lakes are grouped into categories which represent

851-557: The extension of the lake in the past. It was concluded that the lake extended a larger territory in the past. In the case of Llancanelo Lake, the western lacustrine plain was a crucial factor in determining the evolution of the lake. A similar use of drainage areas and lacustrine plain can be found in a research done on the Congo . Sedimentation and drainage data collected through monitoring the Congo's drainage system provide valuable insight into

888-446: The glacial stages and climate periods the region has gone through.   Plain In geography , a plain , commonly known as flatland , is a flat expanse of land that generally does not change much in elevation , and is primarily treeless. Plains occur as lowlands along valleys or at the base of mountains , as coastal plains , and as plateaus or uplands . Plains are one of

925-524: The ice melts and cracks into floating panels; these are blown across the playa by light winds, propelling the rocks in front of them. The stones only move once every two or three years and most tracks last for three or four years. While a dry lake bed is itself typically devoid of vegetation, they are commonly ringed by shadscale , saltbrush and other salt-tolerant plants that provide critical winter fodder for livestock and other herbivores . In southwest Idaho and parts of Nevada and Utah there are

962-571: The lake. It was concluded that two drainage events separated by approximately 65 years led to the final drainage of the lake and the formation of the glaciolacustrine Agassiz-Ojibway Basin. Other locations of glaciolacustrine plains include Lake Erie , Saginaw Bay in Lake Huron , and the Lake Superior lake plain. Lake plains caused by tectonic movements, or epeirogeny, constitute another type of lacustrine plain. Due to tectonic events,

999-463: The land is so flat that crops can thrive. The remaining glacial materials also provide essential nutrients for crop growth and thus boost farm productivity. Lacustrine plains are also valuable in paleoenvironment and paleoclimate studies. By surveying the western lake plain of Llancanelo Lake in Argentina, researchers were able to gather geomorphological data and sedimentary evidence to reconstruct

1036-422: The largest salt flat in the world, comprises 4,085 square miles (10,582 square km). Many dry lakes contain shallow water during the rainy season, especially during wet years. If the layer of water is thin and is moved around the dry lake bed by wind, an exceedingly hard and smooth surface may develop. Thicker layers of water may result in a "cracked-mud" surface and teepee structure desiccation features. If there

1073-429: The major landforms on earth, being present on all continents and covering more than one-third of the world's land area. Plains in many areas are important for agriculture . There are various types of plains and biomes on them. A plain or flatland is a flat expanse of land with a layer of grass that generally does not change much in elevation , and is primarily treeless. Plains occur as lowlands along valleys or at

1110-450: The region experiences. Like any other lake, lakes formed in inland basins are bound to face obliteration. As sediments deposit and accumulate at the bottom of the lake and as water drains due to environmental forces and geologic events, the lake gradually approaches its full state. A lacustrine plain is then formed when drainage reaches completion, and the lake becomes a plain of sediments. One example of inland lake creation in once arid land

1147-400: The rugged surface and smoothens them. Plain resulting from the action of these agents of denudation are called peneplains (almost plain) while plains formed from wind action are called pediplains . Structural plains are relatively undisturbed horizontal surfaces of the Earth. They are structurally depressed areas of the world that make up some of the most extensive natural lowlands on

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1184-977: The smoothness of the surface allows low-clearance vehicles to travel very fast without any risk of disruption by surface irregularities, and the path traveled has no obstacles to avoid. The dry lake beds at Bonneville Salt Flats in Utah and Black Rock Desert in Nevada have both been used for setting land speed records. Lake Eyre and Lake Gairdner in South Australia have also been used for various land speed record attempts. Dry lake beds that rarely fill with water are sometimes used as locations for air bases for similar reasons. Examples include Groom Lake at Area 51 in Nevada and Edwards Air Force Base (known initially as Muroc Dry Lake) in California. Brines from

1221-515: The subsurface of dry lakes are often exploited for valuable minerals in solution. See, for example, Searles Dry Lake and Lithium resources . Under United States law, a "playa lake" may be considered isolated wetlands and may be eligible to enroll in the new wetlands component of the Conservation Reserve Program , enacted in the 2002 farm bill (P.L. 107–171, Sec. 2101). The Burning Man yearly event takes place in

1258-499: The uplift of crusts may occasionally lead to the formation of basins. Later, as water fill the region, a lake is formed. Various factors may contribute to the drainage of the lakes formed in such fashion, and the sediments form a large, flat plain where the lakes once existed. Lacustrine plains formed by differential uplift can be found in multiple locations, and they are most commonly seen in Africa. The Nile drainage system, for example,

1295-437: The water in the lake is lost, leaving behind a level land of sediments. The resulting plain is an area of flat land which is often rich in fine-grained sediments. Depending on geologic and climatic factors, the once-lake region may turn into a desert or wetland. In other cases, lacustrine plains may have agricultural value. The origins of lacustrine plains are lakes formed under different circumstances. Lake plains resulting from

1332-424: The west, Kochia prostrata , also poses a significant threat to playas and their associated rare species, as it capable of crowding out native vegetation and draining a playa's standing water because of its root growth. The extremely flat, smooth, and hard surfaces of dry lake beds make them ideal for fast motor vehicles and motorcycles. Large-sized dry lakes are excellent spots for pursuing land speed records , as

1369-611: The western United States. This term is used e.g. on the Llano Estacado and other parts of the Southern High Plains and is commonly used to address paleolake sediments in the Sahara like Lake Ptolemy . In South America, the usual term for a dry lake bed is salar or salina , Spanish for salt pan . Pan is the term used in most of South Africa. These may include the small round highveld pans, typical of

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