Isotopic and Hydrochemical Analysis of the Ghis-Nekor Aquifer Morocco: Origin of Salinity and Groundwater Quality

Abstract

The chemical characterization of the Ghis-Nekor aquifer has attracted significant attention from researchers in Morocco. It is a crucial indicator of the environmental situation and the socio-economic development of this Moroccan region. Indeed, it helps decision makers to conduct a conscious and sustainable management. The primary objective of this study is to investigate the origin of salinity using isopoly elements such as Stronstium and Bromide and to evaluate the physicochemical quality of groundwater in the Ghis-Nekor aquifer region and to determine the sources of pollution in order to establish maps of the qualities of the Ghis-Nekor water table. For this reason, of Ghis-Nekor aquifer 19 samples were examined during the month of July 2023, in terms of isotopic elements such as bromine (Br) and strontium (Sr) et tantalum (Ta) (03 samples), and in terms of physico-chemical parameters such as pH, temperature, electrical conductivity (EC), Chlorides, Nitrates, Ammonium, Nitrite, Sulfates, Sodium, Potassium, Bicarbonates, Calcium, orthophosphates and Magnesium . The spatial distribution of the results was visualized through thematic maps generated using a Geographic Information System (GIS), offering crucial insights for decision-making processes related to water resource management in the region.The water temperature varies between 15.1 and 49°C. The pH is close to neutral, varying between 6.65 and 7.86. The waters are classified into three distinct chemical facies: chlorinated and sulfated calcic-magnesium facies, bicarbonated calcic-magnesium facies, and chlorinated sodium-potassium facies.The degradation of water quality in the aquifer of the basin of Ghis-Nkour could have geological and anthropogenic origins. The analysis of bromide and strontium contents allows to discriminate the origin of salinity anomalies. Molar ratios such as Cl/Br, Br/Cl, and Sr/Ca are employed to distinguish areas influenced by geological factors, such as the leaching of salt formations and facies, from those impacted by anthropogenic activities.