Perspectivas hidrogeológicas e hidrogeoquímicas sobre la mineralización de aguas subterráneas: Un análisis espaciotemporal del acuífero Complejo Terminal en Wadi Righ, sur de Argelia

Groundwater in the Algerian Sahara is an important source of water for various uses. Despite its abundance compared to surface water, it is still confronted to many problems, in terms of overexploitation and quality. Excessive mineralization of this groundwater is a major issue in the Wadi Righ region in northeastern Algerian Sahara. In this paper, we attempt to examine the groundwater mineralization source of the Terminal Complex aquifer and analyze its spatiotemporal trends by combining tools from Geographic Information Systems (GIS) with hydrogeochemical analysis of results from 117 wells between a period of four years (1995, 2012, 2015 and 2017), and 613 groundwater measurements for six years (1998, 2005, 2010, 2013, 2015 and 2017). The groundwater exhibits electrical conductivity values ranging from 2760 to 11200 μS/cm and TDS concentrations between 1934 and 8318 mg/L, indicating strong mineralization gradients from south to north. The dominant hydrochemical facies are SO₄–Cl–Mg–Ca and SO₄–Cl–Na . Hydrogeochemical diagrams reveal that water–rock interaction and evaporite dissolution are the main processes controlling salinity. Spatial mapping of EC, groundwater levels, and saturation indices (SI) indicates a progressive increase in salinity toward Chott Merouane, with an inverse correlation between groundwater level and mineralization. This study provides the first integrated spatiotemporal assessment combining hydrogeochemical and GIS-based approaches to characterize the evolution of groundwater salinity in the Wadi Righ basin, contributing new insight into the link between aquifer depletion and mineralization in the Algerian Sahara.