Hydrogeological assessment of groundwater potential zones using remote sensing, geographical information system (GIS) and aeromagnetic data at Kwara State University, Malete, Nigeria

Abstract

This study involves a hydrogeological assessment of groundwater potential zones at Kwara State University (KWASU), Malete, Nigeria, using remote sensing, geographic information system (GIS), and aeromagnetic data. It employs eight thematic layers, including rainfall, land use/land cover, slope, elevation, drainage network, drainage density, lineament, and lineament density, which are derived from satellite imagery and digital elevation models. The analytical hierarchy process (AHP) was utilized to assign weights and ratings to each factor based on their relative importance in influencing groundwater occurrence. The weighted overlay analysis in GIS was then applied to generate a groundwater potential map. Results indicate that the Kwara State University area is characterized by favourable hydrogeological conditions, including high annual rainfall (~ 1430 mm), flat to gently sloping topography (elevation < 300 m), and vegetation cover with indication of water bodies within the study area, all of which promote infiltration and recharge. Additionally, aeromagnetic data interpretation involved total magnetic intensity (TMI), reduction to equator (RTE), regional-residual separation, various derivative enhancements, depth analysis and magnetic lineament. These techniques revealed structural lineaments trending southwest–northeast of Kwara State University, indicative of faulted or fractured zones that enhance secondary porosity and groundwater storage. Euler deconvolution and source parameter imaging further delineated subsurface structures and estimated depths to magnetic sources, providing critical insight into aquifer geometry and potential recharge zones. The integration of geospatial and geophysical datasets proved effective in delineating groundwater potential zones with improved accuracy for groundwater development, resource management, and sustainable water planning in the study area and similar terrains.