Multidisciplinary approach to understand the salinization of fractured crystalline aquifers in semi-arid region Kreis, M.B. /Taupin, Jean-Denis /Patris, Nicolas /Lachassagne, Patrick Vergnaud-Ayraud, V. Burte, J.D.P. /Leduc, Christian Passos Rodrigues Martins, E. AQUIFERE EAU SOUTERRAINE RESSOURCES EN EAU SALINISATION HYDRODYNAMIQUE PIEZOMETRIE EAU DE SURFACE HYDROGEOCHIMIE In semi-arid areas, groundwater (GW) represents the most reliable resource for water supply. In the semi-arid region of Ceará (Northeastern Brazil), GW of the crystalline fractured aquifers has a salinity higher than expected in this type of environment. This study implemented a multidisciplinary approach based on hydrodynamic (piezometric) and hydrogeochemical (18O, 2H, 3H, 14C, CFC, SF6, Electrical Conductivity, major ions) data to understand the salinization processes. Results demonstrate that GW is generally recent and recharged by meteoric waters mainly through indirect infiltration from evaporated surface water. The study suggests that GW, originally bicarbonated, becomes progressively enriched in chloride due to the dissolution and leaching of salts, during the wet season, which come from meteoric inputs and have precipitated in the unsaturated zone and pond sediments during dryer periods. 2024 text https://www.documentation.ird.fr/hor/fdi:010095089 fdi:010095089 Kreis M.B., Taupin Jean-Denis, Patris Nicolas, Lachassagne Patrick, Vergnaud-Ayraud V., Burte J.D.P., Leduc Christian, Passos Rodrigues Martins E.. Multidisciplinary approach to understand the salinization of fractured crystalline aquifers in semi-arid region. 2024, 385, 393-398 Scientific Assembly of the International Association of Hydrological Sciences, 11., Montpellier (FRA), 2022/05/29-2022/06/03 EN BRESIL ZONE SEMIARIDE