MJSTEM

Abstract

Groundwater constitutes the principal source of freshwater for domestic, agricultural, and industrial uses in many parts of Nigeria, particularly within the Precambrian Basement Complex where groundwater occurrence is largely controlled by weathering and structural discontinuities. This study presents an integrated assessment of groundwater potential within parts of Minna Sheet 164NE, North-Central Nigeria, through the combination of geological mapping, hydrogeological investigations, remote sensing, geoelectrical surveying, and Geographic Information System (GIS)-based weighted overlay analysis. Detailed geological mapping at a scale of 1:25,000 was undertaken to characterize the lithological units and structural features controlling groundwater occurrence, while hydrogeological data were collected from 60 hand-dug wells. Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) data were processed to generate thematic maps of slope, drainage density, and lineament density. In addition, 48 Vertical Electrical Sounding (VES) stations employing the Schlumberger electrode configuration were interpreted to determine weathered layer thickness, weathered layer resistivity, depth to fresh basement, and basement resistivity. The interpreted geoelectrical parameters indicate that weathered layer thickness varies from 1–33 m, weathered layer resistivity from 10–800 Ωm, depth to fresh basement from 2–45 m, and basement resistivity from 1,000 Ωm to over 28,000 Ωm. The integrated GIS-based groundwater potential model delineated areas of varying groundwater potential across the study area. High groundwater potential zones are associated with thick weathered overburden, fractured basement, moderate weathered layer resistivity, low basement resistivity, high lineament density, and gentle slopes, whereas low groundwater potential zones correspond to shallow basement and competent crystalline rocks with limited groundwater storage capacity. The study demonstrates that integrating geological, hydrogeological, remote sensing, geoelectrical, and GIS techniques provides a reliable and cost-effective framework for groundwater exploration and sustainable groundwater resource management within the Nigerian Basement Complex.

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