Hydrochemical considerations for identifying water from basaltic aquifers: The Israeli experience

Abstract

Study region: Yizre’el-Harod-Bet She’an valley, Lower Galilee and Golan Heights, Israel. Study focus: Identification of pure groundwater that infiltrated the widespread alkali olivine basalts in the replenishment areas of the study region. New hydrological insights for the region: The groundwater is characterized by equivalent ratios such as Na/Cl > 1; Na/HCO3− 1; 1000Br/Cl in the range of 1–2.5; δ34Ssulfate 1 and HCO3−/(Ca + Mg + Na + K) > 0.7. Application of these parameters to analyses showing only the main constituents of groundwater reveals that in the study area the contribution of unmixed groundwater from basaltic catchments is largely restricted to the Golan Heights. Mixing of groundwater by interaquifer flow is a common phenomenon all over the area. Keywords: Limestone aquifer, Basaltic-rock aquifer, Golan Heights, Yizre’el-Harod-Bet She’an Valley, Hydrochemistry