CHEMICAL AND ISOTOPIC CHARACTERIZATION OF RAINWATER IN THE BERRECHID BASIN, MOROCCO

A total of 41 rainwater samples were analyzed in order to define the chemical and isotopic input signature of the Berrechid aquifer, Morocco, during March-April 2013 and April 2014. Samples were analyzed for major anions (NO 3 – , SO 4 2– , Cl – ) and stables isotopes ( 18 O, 2 H). The chemical composition of rainwater is potentially influenced by the contribution of anthropogenic activities and sea spray. The computed meteoric water line (dD = 7.78 d 18 O + 10.09; r=0.94) is consistent with that defined at Rabat station. The mean deuterium excess about 10.92‰ close to the value obtained for Atlantic precipitations confirms the oceanic origin identified by the air mass back trajectories. The altitudinal gradient defined as -0.35‰ d 18 O/100m is close to those defined in regional and national scale.