Groundwater ages and reaction rates during seawater circulation in the Dead Sea aquifer

SO4 is removed relatively fast (k=0.8 y−1) due to gypsum precipitation while barite or celestine precipitation removes 226Ra and Ba in a time scale of years (k=0.22 y−1). Similar rates were found for redox-driven reactions, such as U removal (k=0.4 y−1) and Fe and Mn contribution due to the dissolution of oxides (k=0.15 y−1). In the fresh-saline groundwater transition zone, gypsum which precipitated from hypersaline water in higher lake stands, is now being dissolved and enrich the water with SO4.