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Lonar Lake is a saline soda lake located at Lonar in Buldhana district, Maharashtra, India, which was created by a meteor impact during the Pleistocene Epoch and it is the largest and only hyper velocity impact crater in basaltic rock, anywhere found on earth. This lake, which lies in a basalt impact structure, is both saline and alkaline in nature. Geologists, ecologists, archaeologists, naturalists and astronomers have reported several studies on the various aspects of this crater lake ecosystem. Lonar Lake has a mean diameter of and is about below the crater rim. The meteor crater rim is about in diameter. The circular depression bears a saline water lake in its central portion.〔(【引用サイトリンク】title=Lonar Lake, Buldana District, Maharastra )〕 The crater's age is usually estimated to be 52,000 ± 6,000 years (Pleistocene), although a study published in 2010 gives an age of 570,000 ± 47,000 years. The Smithsonian Institution, the United States Geological Survey, Geological Society of India, and University of Sagar and the Physical Research Laboratory have conducted extensive studies about the site. Biological nitrogen fixation was discovered in this lake in 2007.〔Avinash A. Raut and Shyam S. Bajekal; ''Nitrogen Fixing Bacteria from Hypervelocity meteorite impact Lonar Crater;'' in Special Issue of Research Journal of Biotechnology; December 2008 and Avinash A. Raut and Shyam S. Bajekal; ''Nitrogen Fixing Actinomycetes from Saline Alkaline Environment of Lonar Lake: A Meteorite Impact Crater'', in Journal of Environmental Research and Development, Vol.3, No.3, January–March 2009.〕 == Geographical features == A series of low hills surround the basin which has an oval shape (almost round) with circumference at top of about 8 km (five miles). The sides of the basin rises abruptly at an angle of about 75°. At the base, the lake has a circumference of about 4.8 km (three miles). The slopes are covered with tree-savannah, housing teak (''Tectona grandis''), ''Wrightia'' ''tinctoria, Butea monosperma'', and ''Helicteres isora''. Shrub-savannah with ''Acacia nilotica'' and ''Ziziphus spp.'' is covering the crater wall. Along the lake shore non-native ''Prosopis juliflora'' is spreading. The northeastern alluvial terrace, along the dhara river fan, is used for horticulture. Millets, maize, ladies fingers, bananas, and papayas are the main cultivated crops. The water of the lake contains various salts or sodas, and during dry weather when evaporation reduces the water level, large quantities of soda are collected. Two small streams, named Purna and Penganga, drain into the lake, and a well of sweet water is located on the southern side, close to the water's edge.〔() Geology - Formation of the alluvium〕
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