The salts deposited by the lake brine were mineralogically identified by XRD analysis and include not only calcite and dolomite, but also trona ([Na.sub.2]C[O.sub.3] x NaHC[O.sub.3] x 2[H.sub.2]O),
burkeite ([Na.sub.2]C[O.sub.3] x 2[Na.sub.2]S[O.sub.4]), and halite (NaCl), thus confirming the mineralogical similarity between these deposits and those from Wadi Natron in Egypt.
We used data from Shi (2002) to develop relationships for crystal composition as functions of liquid phase composition, and apparent equilibrium expressions for four characteristic crystallization regions (sulfate,
burkeite, dicarbonate, and carbonate).