Multivariate Statistical Analysis and Geochemical Modeling to Characterize the Surface Water of Oued Chemora Basin,Algeria

Multivariate statistical methods and inverse geochemical modeling were jointly used to deduce the genetic origin of chemical parameters of surface water in the Oued Chemora Basin. The analysis of variance indicates that variations of all parameters at the three stations are significant except for pH and T (p > 0.05). R-mode cluster analysis reveals two distinct groups at each station and led to the conclusion that the major ion chemistry in the three stations is derived from organic and artificial fertilizers due to agricultural activities in the area and water–rock interaction. Mineral saturation indices, calculated from major ions, indicate that the surface water is generally super-saturated with carbonate phases, and all the water samples are under-saturated with respect to gypsum, halite, and CO_2(g). In a broad sense, the reactions responsible for the hydrochemical evolution in the Basin fall into three categories: (1) dissolution of evaporite minerals; (2) precipitation of carbonate minerals; and (3) ion exchange.