Tomographic, hydrochemical and isotopic investigations of the salinization processes in the oasis shallow aquifers, Nefzaoua region, southwestern Tunisia

Journal of Earth system science

Aissa Agoun4¹  Daniel Hermitte5⁴  Zohra Kraiem1⁵  Najiba Chkir2²  Kamel Zouari1⁵  Jean Claude Parisot3³ 

[1] Commissariat R´egional au D´eveloppement Agricole (CRDA) de K´ebili, Tunisie.$$;Department of Geography, Laboratory of Radio-Analyses and Environment, BP 1168, 3002 Sfax, Tunisia.$$;CEREGE, UMR IRD 161, Technopˆole de l’Environnement Arbois M´editerran´ee, Domaine du Petit Arbois, Avenue Louis Philibert, BP 80, 13545 Aix en Provence Cedex 04, France.$$;CEREGE, UMR 6635, CEREGE, BP 80, 13545 Aix en Provence Cedex 04, France.$$;National School of Engineers of Sfax, Laboratory of Radio-Analyses and Environment, BP 1173, 3038 Sfax, Tunisia.$$

关键词: Tomography;    drainage;    dissolution;    evaporation;    oasis;    salinization.;   

DOI  :  

学科分类：天文学(综合)

来源: Indian Academy of Sciences

【 摘 要 】

An electrical imaging tomography survey was carried out to identify the lateral and vertical salinity distribution in the oasis shallow aquifers of the Nefzaoua region located in southwestern Tunisia. In addition, hydrochemical and isotopic data were examined to determine the main factors and mechanisms controlling the groundwater chemistry and salinity. Locally, with respect to salinization processes, electrical imaging tomography results show that the storage basins of irrigation excess-water contribute to the increase of the salinity for the major part of the oasis nearby these basins. Major elements distribution and saturation indices indicate that dissolution of evaporites (halite, anhydrite and gypsum) is the main process controlling the groundwater mineralization. Isotopic data highlighted the effect of evaporation in the salinization of these waters. The correlation between the oxygen 18 and the chlorides data confirms the importance of evaporation effect and dissolution as main processes controlling the groundwater mineralization.

【 授权许可】

Unknown