The Morphology of Gypsum Precipitated Under Hyper-saline Conditions – Preliminary Results from Dead Sea - Red Sea Mixtures

Abstract

Solutions of different chemical compositions will precipitate gypsum crystals with different morphology. The dependence of gypsum morphology on the chemical composition can therefore be a tool for interpreting the paleo-chemistry and environments of solutions from which gypsum in the geological record precipitated. In addition, the morphology of the gypsum that will precipitate in the Dead Sea once the Red Sea-Dead Sea conduit is built will determine if the crystals will remain in suspension in the surface brine, thereby leading to “whitening” of the lake. Despite its importance, little is known about the impact of the different parameters on the morphology of gypsum precipitated from natural brines. In the present study we conducted single point batch experiments with mixtures of Dead Sea - Red Sea brines and utilized image processing techniques to study the morphology of the gypsum that precipitated from different solution compositions at different degrees of oversaturation. The results from the first data set towards the understanding of what controls the morphology of gypsum while providing a preliminary tool for the forecast of the future of the Dead Sea are presented here.