Concentration of Potash Salts in Saline Basins

Abstract

Commercially valuable potash salts such as sylvite and langbeinite generally occupy only small parts of evaporite basins, whereas noncommercial potassium-bearing minerals such as carnallite and polyhalite are of more widespread distribution. The processes of concentration of potassium salts probably begin shortly after salt first is precipitated within the basin. As brine is concentrated, very complex solutions are formed which influence the chemical and physical factors of concentration. Environmental and geologic processes at this time further restrict the locations in which the potash-bearing solutions can precipitate. Upon complete evaporation of the seawater and burial of the preserved complex salts, potash salts may be concentrated further and enriched by metasomatic processes. Salts now are precipitating on a reduced scale in limited areas along the continental margins of the ocean basins, inland seas, continental brine lakes, and salt pans. Trace minerals, such as bromine, cesium, and rubidium, are of special interest in saline studies, because they furnish much information on the genetic character of the salts. Argon, commonly found within salt measures where a high concentration of potassium is present, is an element that can be used to determine the age of the salt.