Pink Lake is thought to be a meromictic lake, there is some controversy on this subject. A meromictic lake is one which lacks complete cirrculation. In meromictic lakes the deepest water contains no dissolved oxygen. Sediments are relatively undisturbed and therefore offer a detailed record of the history of the lake. The monimolimnon is the deepest part of the lake, it is the most dense and is not involved in annual circulation. The increased density is due to the accumulation of salts. During spring, summer, and early fall, decomposing organic matter produces a gradual elimination of the oxygen. The anaerobic zone moves upwards during the summer.
Age/Depth Diagram for Pink Lake
From Mott and Farley-Gill (1981)