Great Salt Plains Lake

Great Salt Plains Lake is a reservoir located within the Salt Plains National Wildlife Refuge in Alfalfa County, Oklahoma in the United States named because of the salt flats in the area and for the Salt Fork Arkansas River, which is dammed to form the lake. It is notable for the variety of birds that are attracted to Ralstin Island (not open to the public) and also for the selenite crystals that can be collected along the shoreline. Recent droughts, most notably that of 2011, have had an adverse effect on the future of the lake.On the west edge of the lake, visitors can dig for selenite crystals. These crystals feature an hourglass inclusion which is unique to the Great Salt Plains. Scientists believe that salt was deposited during repeated water-level rises of a shallow sea millions of years ago. The supply of salt is kept intact by saline groundwater that flows just a few feet below the surface. When the water evaporates, a layer of salt remains on the surface. This process also plays a role in the formation of selenite crystals that visitors covet.