This study used hydrodynamic and hydrogeochemical data to understand the salinization processes of the crystalline groundwater (GW) in Ceará, Brazil. Results demonstrate that GW is generally recent and recharged by meteoric waters mainly through localized infiltration. The study suggests that GW, originally bicarbonated, becomes progressively enriched in chloride due to the dissolution and leaching of salts that have precipitated in the unsaturated zone and pond sediments during dryer periods.

This paper presents new measurements (groundwater level and isotopic content) in the Tamanarasset area, in the Algerian Sahara, where previous data are very few. This recent observation significantly increases the understanding of hydrological processes (from rain to wadi flow and groundwater recharge in alluvium). In contrast with the huge nearly fossil Saharan aquifers, the small alluvial resources are renewed and provide an appreciated source of water.