Contribution des approches hydro-chimiques et statistiques à l'étude des eaux souterraines (cas de la nappe alluviale du SEBAOU)

Abstract

TIZI OUZOU is a coastal city; it is located in the northern central part of Algeria about a hundred kilometers east of the capital Algiers. This region is made up of a succession of east / west oriented mountain ranges that trap narrow lluvial plains. The SEBAOU alluvial plain contains the SEBAOU watershed, a considerable and capital water table located in an aquifer of the MIOCENE PLIO-QUATERNARY. Groundwater is contained in alluvial formations, in the form of nested or stepped terraces and originates from the impluvium and runoff from the slopes and adjacent wades.The water flow is north / South; the rainfall depends on the altitude and the sub-humid climate with mild winters. The hydro chemical study of the water in the water table has made it possible to highlight a predominant facies of CALSIQUE MAGNESIAN BICARBONATE; these waters are suitable for irrigation. The statistical approach applied; PIPER diagrams, vertical SHOELLER / BERKALOFF diagram, principal component analysis (PCA), MUSTACHE BOX and correlation matrix. On the hydro chemical data of the alluvial aquifer of SEBAOU, the values of the conductivity (CE) attest to an average mineralization.