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Show 66 PHYSICAL PROPERTIES OF THE GREAT SALT LAKE Color The South Arm of the Great Salt Lake is blue- green, contrasted by the North Arm which is pink due to certain algae and bacteria ( Quinn, 1966). Transparency and Turbidity Brines of the North Arm have low transparency throughout the year, while the transparency of the South Arm varies widely. During the summer, visibility in the South Arm may extend to depths of 20 feet while, during the winter, objects only a few feet deep cannot be seen. The transition from low to high transparency occurs in May, within a period of one day, during which the water temperature is about 55 degrees Fahrenheit. Normally, turbidity is due to suspended particles of algae, silt or clay. However, Great Salt Lake brines are chemically much more complex than most waters, with various ion and salt effects. The turbidity of the shallow South Arm is thought to be due to small suspended particles of anhydrous sodium sulphate, thenardite, which is formed when solid mirabilite loses water by crystallization at 34 degrees Fahrenheit. The particles are finally dissolved when the total dissolved solids concentration of the South Arm decreases in the spring due to dilution by spring runoff. The turbidity of the North Arm is attributed to " red" algae, which increase in numbers during the summer and decrease during winter, increasing and decreasing turbidity. Figure 11 shows the comparison of the turbidity of the North and South Arms. Dissolved Solids Content There are approximately four to six billion tons of dissolved |