Exploration and Evaluation of Groundwater Potential Using Geoelectrical Method in Arid Zones: A Case Study of Majel Bel Abbes Aquifer (West-Central Tunisia)

The region of Majel Bel Abbes, west-central Tunisia, is characterized by a semi-arid to arid climate. Groundwater is the main source of water for domestic, agricultural and industrial purposes in the region. In order to better recognize the architecture and the lithology of the aquifer system of Majel Bel Abbes and evaluate its hydrogeological potentialities, a geophysical study based on electrical prospection was carried out. The latter allowed the delimitation of two potential aquifers including (i) a Plio-Quaternary hydrogeological unit exhibiting 30 to 50 Ω.m resistivity values and variable lithologies that thicken toward the central part of Majel Bel Abbes basin and (ii) a Miocene sandy hydrogeological unit exhibiting ~20 Ω.m resistivity values and acknowledged as Beglia Formation. This unit rests on the Campanian–Maastrichtian limestones of the Abiod Formation that overlays the Cenomanian limestones to the east of the basin and disappears toward their borders. The new results concerning the Majel Bel Abbes basin architecture and their hydrogeological unit lithologies, thickness and potentialities should be considered by the local authorities in the planning and design of new drilling hydraulics wells to ensure safe management of water supplies.