MODELING CHEMICAL SEDIMENTATION IN CLOSED BASINS
The model developed for this study merges EQUIL with a three-dimensional, physical mass balance model that determines basin water chemistry and mineral precipitation in an environment that is in constant flux from a hydrological standpoint. The addition of inflow water, its chemical and volumetric variability and its influence on both delivering solutes to, and diluting lake water is accounted for. The model stores data for inflow, air temperature, evaporation, lake level, lake salinity, lake volume, and precipitated minerals.
Pleistocene-to-Holocene deposits of Searles Lake were chosen to test the model. Searles Lake deposits comprise a well-preserved record of sedimentation in a closed basin (Smith, 1979; 2009). The results of the model, to varying degrees, match the outcrop and subsurface deposits and shed light on brine evolution during transitional lake stages.