 The Black Creek Member at the base consists of halite.The overlying Lower Anhydrite Member consists of microcrystalline anhydrite with minor beds of fine- to medium-crystalline dolomite.The Zama Member at the center consists of fragmental carbonate, and is overlain by the Upper Anhydrite which consists of interbedded microcrystalline anhydrite and fine- to medium-crystalline dolomite.