Hydrochemical characterization of Gareat-El-Tarf plain groundwaters, Northeastern, Algeria

الملخص EN

A hydrochemical study has been conducted on groundwaters of Gareat-El- Tarf plain in order to discriminate the salinity origin.

Achieved findings indicate that waters are of medium salinity, with a conductivity of 1618μS/cm.

A spatial variation in chemical facies suggests that waters chemistry is influenced by a number of factors such as geology, climate and anthropogenic activity.

Waters are bicarbonate-calcic type upstream of the basin and near calcareous outcrops, sulfate-calcic type in the Mio-Plio-Quaternary filling and ultimately become chloride-sodic type on the borders of the Sebkha.

Chloride ion crossing with major ions on binary diagrams suggests that waters salinity would be attributed to water-rock interaction characterized by mineral dissolution and precipitation, as well as cation exchange.

Chemical tracing by trace elements such as strontium suggests that evaporites dissolution contributes to waters salinity of Gareat-El-Tarf plain.

Statistical approach is another tool allowing to classify processes responsible for hydrochemical variability, in function of their significance.

The increase in salinity is mainly due to climate aridity.