Great Salt Lake (GSL) in northern Utah is the world's largest body of significantly salty water.  The saltiness of the lake water ranges from about 6% to 27% (seawater averages 3.5% salinity).  Salt has accumulated in Great Salt Lake for many thousands of years because the basin lacks an outlet.  During the Pleistocene (the last Ice Age), Great Salt Lake extended much, much further than its present ~1700 square miles.  The Pleistocene-aged precursor to GSL is known as Lake Bonneville (actually, four different lake names are used to refer to different stages of the Pleistocene GSL precursor).  At its maximum, Lake Bonneville covered ~20,000 square miles.


Great Salt Lake (looking ~ N) - Silver Island Mountains & the Bonneville Salt Flats from a few miles east of Wendover (a small town on the Utah-Nevada border).



Great Salt Lake, as seen from Saltair, Utah, USA.



Great Salt Lake oolites - the grayish-colored, shoreline sediments here are oolites - calcareous (aragonitic) spheres formed by back-and-forth rolling in the water by wave action and precipitation of CaCO3.  Great Salt Lake is one of the few places ion Earth where modern oolitic sediments can be seen forming in a nonmarine setting.



Mudcracks - modern mudcracks formed in lacustrine evaporitic sediments near Saltair, Great Salt Lake, Utah, USA.



Puckered salt crust surface & gas pockets developed in lacustrine evaporitic sediments near Saltair, Great Salt Lake, Utah, USA.  The gas pockets formed from decay of buried organic matter.



Modern bird carcass impregnated with salt from an evaporated portion of Great Salt Lake, near Saltair, Utah.  Salt is a great preservative, but I've never heard of anyone finding soft-bodied fossils in ancient rock salt beds (not counting still-living halobacteria isolated from late Precambrian & Phanerozoic rock salts).  Is there the potential, though?



Lake Bonneville lake terraces (above & below): ancient lake terraces visible at the northern end of the Oquirrh Mountains, southern margin of Great Salt Lake.



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