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Show HISTORICAL BACKGROUND OF THE GREAT SALT LAKE The Great Salt Lake, located a few miles northwest of Salt Lake City, Utah, between the Great Salt Desert and the Wasatch Mountain Range, is the largest closed- basin lake in the Western Range and the second largest inland body of salt water in the world. It is a remnant of Pleistocene Lake Bonneville, a glacial lake which was once approximately 20,000 square miles, covering most of northwestern Utah with fringes extending into eastern Nevada and southeastern Idaho. At its greatest height, Lake Bonneville extended 140 miles from east to west and 285 miles from north to south. Bonneville Basin, like the Great Basin of which it is a part, actually consists of a group of basins with different elevations, separated by mountains and hills. During the Pleistocene epoch ( the past 70,000 to 100,000 years) there were wet pluvial periods which caused these smaller basins to fill, overflowing into others which in turn overflowed into others, forming larger and larger lakes which merged to form Lake Bonneville. As the climate changed toward the end of the Pleistocene epoch, the Lake became smaller, with evaporation and inflow continuously changing the size and salinity of the Lake since then. Several times, the Lake reached a maximum depth of more than 1,000 feet, and at least once almost dried completely. The east bench of Salt Lake City is an old shoreline of the Lake's Bonneville Level, approximately 5200 feet elevation. The Provo Level, 4825 feet and Stansbury Level, 4400 feet, are two other prominent levels of the Lake. |