This study uses electrical resistivity tomography (ERT) to characterize the shallow subsurface of the Ribat El-Kheir plateau and assess structural features that may influence groundwater circulation in the Liassic limestone aquifer. Five ERT profiles were interpreted to map resistivity contrasts between the limestone, Triassic clay-rich units and deeper Triassic formations. The interpreted models show resistivities from approximately 3 to more than 5000 Ω·m. The limestone reaches about 40 m in thickness in the southern sector and thins to approximately 5–20 m toward the west and north. A resistivity discontinuity near the 370 m station on Profiles 2 and 3 is interpreted as a fault-related zone; a conductive interval about 10 m wide on Profile 3 may represent intense fracturing. These features identify a potential target for follow-up geological and hydrogeological investigation. ERT constrains subsurface structure but does not, by itself, demonstrate groundwater occurrence, hydraulic connectivity or well productivity.