The study conducted in the southern part of Arochukwu LGA, Abia State, Nigeria, explores subsurface lithology and aquifer characteristics using geoelectrical methods. This research aims to delineate subsurface layers and assess groundwater potential using the Vertical Electrical Sounding (VES) method. A geoelectrical survey employing the VES method was carried out at multiple points within the study area. The resistivity data obtained were analyzed to construct subsurface profiles and identify key lithological layers. The survey identified four distinct subsurface layers. The topsoil layer exhibited high resistivity and minimal thickness, indicating low groundwater potential. Beneath this, a sandy clay layer was observed, acting as an aquitard due to its moderate resistivity and restrictive water movement. The primary aquifer, identified as the third layer, showed lower resistivity, signifying its water-bearing capacity. The deepest layer, composed of gravel, had high resistivity and thickness, indicating good potential for groundwater storage but posing accessibility challenges. The apparent resistivity values ranged from 0.2 Ωm to 17.4 Ωm, with variations across different VES points indicating diverse subsurface conditions. Depth to aquifer varied from 15.7 meters to 34.2 meters, suggesting geological heterogeneity. Aquifer thickness ranged from 14.2 meters to 28.7 meters, highlighting differences in groundwater storage capacity. The Dar Zarrouk parameters, including longitudinal conductance, transverse resistance, hydraulic conductivity, and transmissivity, further elucidated the aquifer properties, revealing significant spatial variability. The study identifies the primary aquifer as a significant groundwater source, emphasizing the need for site-specific strategies for effective groundwater extraction. The protective capacity and soil corrosivity ratings provide insights for sustainable groundwater management and infrastructure planning. This research provides a comprehensive geoelectrical assessment of the subsurface layers and aquifer characteristics in Arochukwu LGA, Abia State, offering crucial data for groundwater management and development strategies in the region. These findings highlight the critical need for detailed subsurface investigations to accurately characterize groundwater resources. The geoelectrical method, particularly VES, proves to be a valuable tool in hydrogeological studies, enabling the identification of aquifers and their properties. The identified aquifer's water-bearing capacity, coupled with its spatial variability, underscores the importance of tailored groundwater extraction and management practices. This study contributes to a deeper understanding of the subsurface environment in Arochukwu LGA, aiding in the sustainable development and utilization of groundwater resources. Such research is vital for ensuring water security and supporting the socio-economic development of the region, addressing both current and future water demands.
Odoh et al. (Tue,) studied this question.