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How did Lake Bonneville leave behind Great Salt Lake and nearby salt lakes?

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tectonic basins and rift valleys Escarpments of the Great Rift Valley rising above the plain north of Samburu Game Preserve, central Kenya. Beisa oryxes graze in the foreground.

Lake Bonneville was a vast prehistoric freshwater lake that covered much of western Utah and parts of Nevada and Idaho during the Pleistocene Epoch. During glacial periods, the lake was maintained by high water levels and had an outlet that drained into the Snake River and eventually the Pacific Ocean.12

As the climate shifted during interglacial and postglacial periods, water levels receded and the lake lost its external drainage outlet. Without an outlet, the lake became an endorheic (closed) basin where water could only escape through evaporation. Because the rivers feeding the basin continued to carry dissolved mineral salts into the lake, these salts became trapped and concentrated as the water volume decreased.23

This process left behind smaller, saline remnants, most notably the Great Salt Lake, as well as the Sevier Dry Lake and the Bonneville Salt Flats, which are remnants of the former lake bed.12