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25-512: Lake Maitland is a dry salt lake located approximately 100 kilometres (62 mi) south east of Wiluna , in the Mid West region of Western Australia . The Lake Maitland project was being pursued by Canadian company Mega Uranium. Mega teamed up with Australian company Toro Energy Pty Ltd in 2013, Toro Energy have an active proposal to mine uranium at Lake Way - incorporate two uranium deposits - Lake Way and Centipede. Toro Energy submitted

50-575: A channel would allow water from the sea to flow inland. The hope was that this would facilitate trade and naval warfare, as well as change the climatic conditions of the Sahara. Chotts have also been studied because they are believed to be an Earth analogue to similar features on the planet Mars . Although there are considerable differences between terrestrial and Martian geology, some features on Mars are also believed to be evaporite basins, and consequently share at least some features of chotts. One example of

75-513: A decline from 1992 to 2020. Chott In geology , a chott , shott , or shatt ( / ˈ ʃ ɒ t / ; Arabic : شط , romanized :  šaṭṭ , lit.   'bank, coast') is a salt lake in Africa 's Maghreb that stays dry for much of the year but receives some water in the winter. The elevation of a chott surface is controlled by the position of the water table and capillary fringe , with sediment deflation occurring when

100-673: 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

125-582: 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 ,

150-402: 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

175-400: 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,

200-600: 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

225-653: A referral to the WA and Federal Government in 2014 to include the Lake Maitland and Millipede deposits to the existing proposal to mine Lake Way and Centipede. The proposal is to now to mine 4 deposits across 2 lake systems. It is one of four advanced uranium mining projects, the others being the Lake Way uranium project , Yeelirrie uranium project , and Kintyre uranium deposit . The 750-tonne (740-long-ton; 830-short-ton) U 3 O 8 Lake Maitland project, pursued by Mega Uranium, and

250-593: A source of loose sand, aeolian deposition can also play a role in the sedimentary deposition on the chott surface. As many lie below sea level, the chotts of the Sahara were viewed by some European colonialists and engineers as an opportunity to create an inland sea in the Sahara Desert (known by many as the " Sahara Sea ") by cutting a canal to the Mediterranean Sea (or in some cases, the Atlantic Ocean). Such

275-582: A year. Dry lake 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

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300-428: 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

325-521: Is located approximately 30 km north of the Bronzewing Gold Mine . A 35 percent stake in the mine is held by Japanese consortium Japan Australia Uranium Resources Development Co (JAURD). JAURD is jointly owned by Kansai Electric Power , Kyushu Electric Power and Shikoku Electric Power , who, between them, operate nuclear power plants. The mine, expected to have a mine live of ten years, is scheduled to produce 1.65 million pounds of uranium oxide

350-600: 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

375-594: 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

400-463: The 1980s, but progress was halted because of a dispute between the joint owners at the time, but also saw frequent changes in ownership. After some more drilling in 2005 by Redport Ltd, the company was taken over by Mega Uranium in December 2006, who continued drilling and exploration efforts in 2007-08. The future mine, while remote, benefits from existing infrastructure in the region from other mines. It

425-597: The 680 tonnes U 3 O 8 Centipede–Lake Way project undertaken by Toro Energy, located at Lake Way . The uranium mining projects in Western Australia have attracted opposition from organisations like the Anti-Nuclear Alliance of Western Australia, which have attempted to put a hold on them before they reach active mining stage. The Lake Maitland uranium deposit was first discovered in 1972 by Asarco Australia . The deposit saw limited exploration efforts in

450-524: 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

475-422: 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

500-952: 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

525-503: 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

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550-403: The surface of the sediment. In fact, annual evaporation rates per year in chotts often exceed 20 times the annual precipitation rate. This salt accumulation can lead chotts to have particularly high albedo , albeit with comparable variability as well. While evaporite deposition predominates on chotts, in more humid climatic periods, layers of mud can be deposited on the chott surface. When near

575-611: The water table falls and sediment accumulation occurring when the water table rises. They are formed—within variable shores—by the spring thaw from the Atlas mountain range , along with occasional rainwater or groundwater sources in the Sahara , such as the Bas Saharan Basin . The chotts of the Sahara are fed intermittently during periods of infrequent rainfall. They are subject to a high evaporation rate, hence salts eventually accumulate in

600-424: 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

625-543: 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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