Bonneville Salt Flats, UT (No. 5)
Humans have lived in the Great Basin for thousands of years. Excavations at nearby Danger Cave have proven occupation of the area as early as 10,300 years ago. While Native Americans adapted to the desert environment, more recent arrivals found the area less hospitable.
By 1824, Jim Bridger and other mountain men explored the Great Salt Lake desert region. The first recorded crossing of the desert was made in 1845 by Captain John C. Fremont's survey party, with scouts Kit Carson and Joe Walker. Early the next year, 23 year old Lansford Hastings retraced Fremont's trail across the salt plain. Joe Walker's writings warned emigrants not to attempt the untried route; however, Hastings convinced several emigrant parties to follow him.
Despite Walker's warnings, the Donner-Reed party, seeking a shortcut to California in 1846, attempted the "Hastings Cutoff". They failed to take enough water and lost a critical number of oxen. Four of their wagons were abandoned just 10 miles northeast of the salt flats. Time was lost, and the delay resulted in their late arrival to the Sierra Nevada Mountains and their tragic winter.
Later, in 1910, the first permanent crossing of the Bonneville Salt Flats was completed when the Southern Pacific Railroad was built linking Salt Lake City and San Francisco.
Although he never visited the salt flats, the area is named in honor of Captain B.L.E. Bonneville, whose expeditions in the 1830's proved the area was part of an ancient basin.
During the last Ice Age, about 15,000 years ago, Lake Bonneville was the size of Lake Michigan. It covered one-third of present day Utah and parts of neighboring states. You can see traces of the shorelines, representing different levels of the receding lake, etched into the mountains surrounding the salt flats.
The Bonneville Salt Flats and the Great Salt Lake are remnants of ancient Lake Bonneville. Wind and water combine to create the flat surface of salt. Each winter, a shallow layer of standing water floods the surface of the salt flats. During spring and summer, the water slowly evaporates while winds smooth the surface into a vast, nearly perfect flat plain.
The salt surface contains potassium, magnesium lithium and sodium chloride (common table salt).
