Statistical categorization geochemical modeling of groundwater in Ain Azel plain (Algeria)

Abstract

Water analysis data of 54 groundwater samples from 18 uniformly distributed wells were collected during three campaigns (June, September and December 2004). Q-mode hierarchical cluster analysis (HCA) was employed for partitioning the water samples into hydrochemical facies. Interpretation of analytical data showed that the abundance of major ions was identified as follows: Ca ⩾ Mg > Na > K and HCO 3 ⩾ Cl > SO 4. Three major water facies are suggested by the HCA analysis. The samples from the area were classified as recharge area waters (Ca–Mg–HCO 3 water), transition area waters (Mg–Ca–HCO 3–Cl water), and discharge area waters (Mg–Ca–Cl–HCO 3 water). Inverse geochemical modeling suggests that relatively few phases are required to derive the water chemistry in the area. In a broad sense, the reactions responsible for the hydrochemical evolution in the area fall into two categories: (1) evaporite weathering reactions and (2) precipitation of carbonate minerals.