The study conducted in the southern part of Arochukwu LGA, Abia State, Nigeria, offers significant insights into the subsurface lithology and aquifer characteristics using geoelectrical methods. This research aims to characterize the subsurface aquifer system and assess its groundwater potential using Vertical Electrical Sounding (VES). The study utilized geoelectrical methods, specifically VES, to investigate subsurface lithology and aquifer properties at multiple points. Key parameters, such as apparent resistivity, depth, and thickness, were analyzed to evaluate groundwater potential. The results revealed a dominant curve type of QQ, consisting of four distinct layers. The topmost layer, composed of topsoil, exhibited minimal thickness and relatively high resistivity. The second layer, consisting of sandy clay, showed moderate resistivity. The primary aquifer, identified as Layer 3, was characterized by lower resistivity, indicating its potential for groundwater storage. The deepest layer, composed of gravel, exhibited high resistivity and considerable thickness. VES 1, located at coordinates 5.71361 latitude and 7.85167 longitude, exhibited the lowest apparent resistivity (0.70 Ωm), the greatest depth (79.40 meters), and the highest thickness (55.10 meters), indicating excellent aquifer potential. VES 5 exhibited the highest apparent resistivity (17.40 Ωm) and relatively shallower depth (27.20 meters) and thickness (21.90 meters), suggesting less favorable conditions for groundwater extraction. The spatial distribution of apparent resistivity revealed significant variability across the study area. The northwestern part exhibited the lowest resistivity values, indicating higher groundwater saturation and suggesting a more productive aquifer. Depth and thickness data further refined the understanding of the aquifer system, with the deepest and thickest aquifers found in the western part, particularly at VES 1. This location's substantial depth and thickness indicate a high-capacity aquifer, supporting sustainable groundwater extraction. The geoelectrical survey provided a detailed characterization of the subsurface aquifer system. The spatial maps and data tables highlighted significant variations in apparent resistivity, depth, and thickness, offering valuable insights for groundwater management. Prioritizing areas with low resistivity, substantial depth, and thickness can enhance the efficiency and sustainability of groundwater extraction. This study underscores the critical role of geophysical methods in aquifer assessment and the importance of tailored management strategies based on detailed subsurface investigations. The integrated analysis offers a comprehensive understanding of the aquifer characteristics, guiding effective groundwater resource management in southern Arochukwu LGA.
Odoh et al. (Tue,) studied this question.