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The Great Salt Lake, located in the northern part of the U.S. state of Utah, is the largest salt water lake in the Western Hemisphere,〔(Great Salt Lake ). ''Encyclopædia Britannica Online''〕 and the fourth-largest terminal lake in the world.〔(Great Salt Lake, Utah ). ''U.S. Geological Survey''.〕 In an average year the lake covers an area of around ,〔 but the lake's size fluctuates substantially due to its shallowness. For instance, in 1963 it reached its lowest recorded level at 950 square miles (2,460 km²), but in 1988 the surface area was at the historic high of .〔 In terms of surface area, it is the largest lake in the United States that is not part of the Great Lakes region. The lake is the largest remnant of Lake Bonneville, a prehistoric pluvial lake that once covered much of western Utah. The three major tributaries to the lake, the Jordan, Weber, and Bear rivers together deposit around 1.1 million tons of minerals in the lake each year.〔 As it is endorheic (has no outlet besides evaporation), it has very high salinity, far saltier than seawater, and its mineral content is constantly increasing. Its shallow, warm waters cause frequent, sometimes heavy lake-effect snows from late fall through spring. Although it has been called "America's Dead Sea",〔(Great Salt Lake — a lively recreational jewel ). Lynn Arave, ''Deseret News.''〕 the lake provides habitat for millions of native birds, brine shrimp, shorebirds, and waterfowl, including the largest staging population of Wilson's phalarope in the world.〔(Birds and Great Salt Lake ). ''U.S. Geological Survey''.〕 ==Origin== Great Salt Lake is a remnant of a much larger prehistoric lake called Lake Bonneville. At its greatest extent, Lake Bonneville spanned , nearly as large as present-day Lake Michigan, and roughly ten times the area of the Great Salt Lake today.〔 Bonneville reached at its deepest point,〔 and covered much of present-day Utah and small portions of Idaho and Nevada during the ice ages of the Pleistocene Epoch. Lake Bonneville existed until about 16,800 years ago, when a large portion of the lake was released through the Red Rock Pass in Idaho. With the warming climate, the remaining lake began to dry, leaving the Great Salt Lake, Utah Lake, Sevier Lake, and Rush Lake behind.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Great Salt Lake」の詳細全文を読む スポンサード リンク
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