Hydrochemistry and isotopic exploration for a karstic aquifer in a semi-arid region: case of Cheria Plain, Eastern Algeria

Groundwater from karst aquifers is among the world’s most important sources of drinking water supplies, and the hydrochemical characteristics of karst water are affected by both natural environment and people. Therefore, the study of karst groundwater hydrochemistry and its solutes’ sources is very important to ensure the normal function of life support systems. In this paper, hydrogeochemistry and isotope hydrogeology approaches have been used to investigate the karst groundwater systems at Cheria region in recent years. Hydrochemical types of karst groundwater in the study area were mainly of the Ca–HCO3 type or Ca(Mg)–HCO3 type indicating that weathering of limestones and dolostones is the most important factor controlling the hydrogeochemistry of underground waters, and weathering of sulfate and evaporite rocks is less important. Moreover, the precipitation and human activities also have a definite influence on the hydrogeochemistry of underground waters in the region studied. Using stable isotope analysis data, δ18O and δ2H relationships show that all waters are meteoric in origin.