IJG  Vol.4 No.8 A , October 2013
Hydrochemical and Isotopic Study of Groundwater in the North Djeffara Aquifer, Gulf of Gabès, Southern Tunisia

The northern Djeffara aquifer system is located in the southeast ofTunisiaand extends over an area of400 km2. This multilayer system of aquifers is essentially recharged by infiltration of rain and by groundwater of the Continental Inter-calaire aquifer, and occurs mainly at two levels between 0 and180 mdepth that belong to the Mio-Pliocene to form the aquifers. A combined hydrogeologic and isotopic investigation using several chemical and isotopic tracers’, i.e., major ions, δ18O, δ2H and tritium, was carried out in order to determine the sources of water recharge to the aquifer and the origin of salinity. The results of geochemical and isotopic studies show that the groundwater in the south of the study area represents a mixture of the Djeffara aquifer groundwater and locally infiltrates modern recharge. In the northern part, the groundwater which resembles that of the Sekhira aquifer originates from locally infiltrated rain and runoff. The salinity of the groundwater is caused by dissolution of evaporate rocks (gypsum and halite minerals) in the aquifer system. The stable isotopes data do not support the hypothesis of mixing with seawater.

Cite this paper
M. Hamouda, A. Mamou, J. Bejaoui and K. Froehlich, "Hydrochemical and Isotopic Study of Groundwater in the North Djeffara Aquifer, Gulf of Gabès, Southern Tunisia," International Journal of Geosciences, Vol. 4 No. 8, 2013, pp. 1-10. doi: 10.4236/ijg.2013.48A001.
[1]   J. W. Lloyd, K. W. F. Howard, N. R. Pacey and J. H. Tellam, “The Value of Iodine as Parameter in the Chemical Characterization of Groundwaters,” Journal of Hydrology, Vol. 57, No. 3-4, 1982, pp. 247-265.

[2]   C. A. J. Appelo and D. Postma “Geochemistry, Groundwater and Pollution” Vol. 536, Balkema, Rotterdam, 1993.

[3]   I. Cartwright, T. R Weaver, S Fulton, C. Nichol, M. Reid and X. Cheng, “Hydrogeochemical and Isotopic Constraints on the Origins of Dryland Salinity, Murray Basin, Victoria, Australia,” Applied Geochemistry, Vol. 19, No. 8, 2004, pp. 1233-1254.

[4]   P. D. Glynn and L. N. Plummer, “Geochemistry and the Understanding of Groundwater Systems,” Hydrogeology Journal, Vol. 13, No. 1, 2005, pp. 263-287.

[5]   ERES, “Etude des Ressources en eau du Sahara Septentrional, Algérie, Tunisie,” Rapport sur les résultats du projet conclusions et recommandations, Vol. 44, UNESCO, Paris, 1972.

[6]   R. Gonfiantini, G. Conrad, J. Ch. Fontes, G. Sauzy and B. R. Payne, “Isotopic Investigation of the Continental Intercalaire Aquifer and Its Relation to Other Aquifers in Northern Sahara,” Isotope Techniques in Groundwater Hydrology, Proceedings Series, Vienna, 1974, pp. 227-241.

[7]   J. C. Fontes, R. Coque, L. Dever, A. Filly and A. Mamou, “Paléohydrologie Isotopique de l’oued el Akarit (sud Tunisie) au Pleistocène Supérieur et à l’holocène (Paleohydrology Isotopic Wadi el Akarit (southern Tunisia) Upper Pleistocene and Holocene,” Palaeogeography, Palaeoclimatology, Palaeoecology, Vol. 43, No. 1-2, 1983, pp 4-62. http://dx.doi.org/10.1016/0031-0182(83)90047-0

[8]   A. Mamou, “Caractéristiques et évaluation des ressources en eau du sud tunisien,” Thèse de Doctorat d’Etat Es Sciences à l’Univ Paris-Sud (Characteristics and Evaluation of water Resources in Southern Tunisia),” PhD State Es Sciences, University of South-Paris, 1990, 425 p.

[9]   W. M. Edmunds, P. Shand, A. H. Guendouz, A. S. Moulla, A. Mamou and K. Zouari, “Recharge Characteristics and Groundwater Quality of the Grand Erg Oriental Basin,” British Geological Survey, Wallingford, Final report, 1997, 9 p.

[10]   W. M. Edmunds, A. Guendouz, A. Mamou, A. Moulla, P. Shand and K. Zouari, “Groundwater Evolution in the Continental Intercalaire Aquifer of Southern Algeria and Tunisia: Trace Element and Isotopic Indicators,” Applied Geochemistry, Vol. 18, No. 6, 2003, pp. 805-822.

[11]   A. Guendouz, A. S. Moulla, W. M. Edmunds, K. Zouari, P. Shand and A. Mamou, “Hydrogeochemical and Isotopic Evolution of Water in the Complexe Terminal Aquifer in the Agerian Sahara,” Hydrogeology Journal, Vol. 11, No. 4, 2003, pp. 483-495.

[12]   A. F. Mekrazi, “Contribution à l’étude Hydrogéologique de la Région de Gabès-Nord Thèse de 3ème Cycle Présentée à l’Univ de Bordeaux I,” Contribution to the hydrogeological Study of the Gabès Region North 3rd Cycle Thesis, University of Bordeaux I, 1975.

[13]   R. Rouatbi, “Contribution à l’étude hydrogéologique du Karst enterré de Gabès Sud Tunis, BIRH, (Contribution to the Study of Hydrogeological Buried Karst of South Gabes),” PhD Thesis, University of Montpellier, 1967, 235 p.

[14]   R. Trabelsi, M. Zairi and H. Ben Dhia, “Groundwater Salinization of the Sfax Superficial Aquifer, Tunisia,” Hydrogeology Journal, Vol. 15, No. 7, 2007, pp. 1341-1355.

[15]   R. Trabelsi, A. Kacem, K. Zouari and K. Rozanski “Quantifying Regional Groundwater Flow between Continental Intercalaire and Djeffara Aquifers in Southern Tunisia Using Isotope Methods,” Environmental Geology, Vol. 58, No. 1, 2009, pp. 171-183.

[16]   J. Makni, F. Ben Brahim, S. Hassine, S. Bouri and H. Ben Dhia “Hydrogeological and Mixing Process of Waters in Deep Aquifers in Arid Regions: South East Tunisia,” Arabian Journal of Geosciences, 2013.

[17]   S. Epstein and T. K. Mayeda, “Variations of 18O Content of Waters from Natural Sources,” Geochimica et Cosmochimica Acta, Vol. 4, No. 5, 1953, pp. 213-224.

[18]   M. L. Coleman, T. J. Shepherd, J. J. Durham, J. E. Rouse and G. R. Moore, “Reduction of Water with Zinc for Hydrogen Isotope Analysis,” Analytical Chemistry, Vol. 54, No. 6, 1982, pp. 993-995.

[19]   T. B Coplen, “Normalization of Oxygen and Hydrogen Isotope Data,” Chemical Geology, Vol. 72, No. 4, 1988, pp. 293-297.

[20]   C. B. Taylor and P. Schwarz, “Deionization Procedure for Large Quantities of Tritium-Free Water Using an Ion-Exchange Column,” The International Journal of Applied Radiation and Isotopes, Vol. 28, No. 6, 1977, pp. 605-605. http://dx.doi.org/10.1016/0020-708X(77)90047-3

[21]   B. F. Jones, A. Vengosh, E. Rosenthal and Y. Yechieli, “Geochemical Investigations,” In: J. Bear, et al. Eds., Seawater Intrusion in Coastal Aquifers—Concepts, Methods and Practices, Kluwer Academic Publishers, Dordrecht, 1999, pp. 51-72.

[22]   L. N. Plummer, B. F. Jones and A. H. Truesdell, “WATEQF, a Fortan IV version of WATEQ, a Computer Program for Calculating Chemical Equilibrium of Natural Waters,” US Geological Survey, Water Resources Research, 1976.

[23]   A. Vengosh and A. Ben-Zvi, “Formation of a salt plume in the Coastal Plain Aquifer of Israel: the Be’er Toviyya region,” Journal of Hydrology, Vol. 160, No. 1-4, 1994, pp. 21-52.

[24]   A. R. H. Swan and M. Sandilands, “Introduction to Geological Data Analysis,” Blackwell, Oxford, 1995.

[25]   C. I. Voss and W. Wood, “Synthesis of Geochemical, Isotopic and Groundwater Modeling Analysis to Explain Regional Flow in a Coastal Aquifer of Southern Oahu, Hawaii,” Mathematical Models and Their Applications to Isotope Studies in Groundwater Hydrology: Proceeding of a Final Research Co-Ordination Meeting, IAEA, Vienna, 1994, pp. 147-178.

[26]   T. Vitvar, P. K. Aggarwal and J. J. McDonnell, “A Review of Isotope Applications in Catchment Hydrology,” In: P. K. Aggarwal, J. Gat and K. F. O. Froehlich Eds., Isotopes in the Water Cycle: Past, Present and Future of a Developing Science, 2005, pp. 151-170.

[27]   M. Maliki, “Etude Hydrogéologique, Géochimique et Isotopique des Eaux de la Nappe Profonde de Sfax, Thèse de 3ème Cycle de la Faculté de Sciences de Tunis,” (Hydrogeological Study, Geochemical and isotopic waters of the deep groundwater Sfax), Thesis Faculty of Sciences of Tunis, 2000.

[28]   H. Celle-Jeanton, K. Zouari, Y. Travi and A. Daoud, “Isotopic Characterisation of the Precipitation in Tunisia. Variations of the Stable Isotope Compositions of Rainfall Events Related to the Origin of Air Masses,” Earth and Planetary Science Letters, Vol. 333, 2001, pp. 625-631.

[29]   J. F. Aranyossy and A. Mamou, “Contribution of Nuclear Techniques in the Study of Aquifers South Tunisia,” Project Report, RAF/8/007 IAEA, Vienna, 1985.

[30]   M. F. Ben Hamouda, H. Ben Kraiem, A. Mahjoub, B. Labidi, R. Ghoudi, H. Hamrouni, H. Nasr, K Zouari, K. Froehlich, M. I. Sajjad and E. Garcia-Agudo, “Geochemical and Isotopic Characterization of Groundwater Resources in El Hicha Region, Gabes, Southern Tunisia” Proceeding of the International Conference on the Study of Environmental Change Using Isotope Techniques, Vienna, 2001, pp. 457-459.

[31]   A. Zuber, “Mathematical Models for the Interpretation of Environmental Radioisotopes in Groundwater Systems,” In: B. P. Fritz and Fontes, J.C., Eds., Handbook of Environmental Isotope Geochemistry, 1st Edition, Vol. II. The Terrestrial Environment, Elsevier Science Publishers, New York, 1986, pp. 1-59.