Integrating conventional and remote sensing with DC resistivity datasets to map groundwater potential areas using the analytical hierarchy process method, North Wadi Diit, Egypt

This study investigates the groundwater potential (GWP) in Wadi Diit, an arid region with promising resource development prospects, by integrating topographic, hydrogeological, and mineralogical parameters. To analyze the study area, a combination of conventional methods, remote sensing data from Sentinel-2, ASTER-GDEM, and ASTER-L1B, as well as DC resistivity datasets was utilized. The study region comprises Precambrian, Tertiary, and Quaternary surface rock units, supporting lithosol and Yermosol soil types. Barren lands dominate the landscape, while the southern portion experiences higher rainfall. Nine thematic layers (quartz index, carbonate index, slope, rainfall, drainage density, topographic wetness index, lineament density, land cover, and mafic index) were classified and weighted using GIS-based analytical hierarchy process, achieving a model accuracy of 0.0959. The GWP zones were categorized into very low (4.53%), low (17.33%), moderate (27.05%), high (27.79%), and very high (23.3%) categories, predominantly falling within moderate to very high classifications. Validation through hydrogeological data from 11 wells and a receiver operating characteristic curve analysis (area under curve = 0.8) confirmed the model's reliability. DC resistivity measurements were conducted at nine vertical electrical sounding (VES) sites using a Schlumberger array (AB/2 = 500 m) along two profiles. The data were analyzed using various inversion techniques, including unconstrained 1D-VES, laterally constrained inversion (LCI-VES), spatially constrained inversion (SCI-VES), and 2D-VES inversions. A 0.3 constraint factor was applied to assess the accuracy of the model parameters, as their STDF derived from SCI-VES data were determined to be well-resolved. The SCI-VES and 2D-VES inversion results identified four distinct geological layers; unconsolidated surface deposits, gravelly-sand sediments of fresh-brackish Quaternary aquifer (30-384 Ω m and 3.7-15.9 m depth), saturated clayey-sand deposits, and saline Fractured Basement aquifer (10-137 Ω m and 33-90.4 m depth). The region exhibits a complex geological structure, characterized by an uplifted Fractured Basement aquifer trending southeast and southwest as indicated by 2D-VES models. The north-central region emerges as the most favorable location for substantial GWPZ, making it strategically ideal for the installation of additional water wells.