Geophysical assessment of groundwater resources in Ikpere – Ekiti, South Western Nigeria

The study employed the Natural Audio Frequency Telluric Method (NAFTM) to investigate subsurface geophysical properties in Ikpere-Ekiti, southwestern Nigeria. Profile maps and resistivity curves revealed predominantly H, KH, HK, and A-type curves, indicating variations in lithology, fluid content, and boundary interfaces. Results show topsoil thicknesses of 0.3–0.6 m, overburden depths of 3.36–31.88 m, and weathered layers extending up to 56.65 m, with higher weathering observed at Igbede, Ilesemon, and GRA. These conditions favor groundwater accumulation, supported by static water levels of 2.9–9.2 m and evidence of a phreatic unconfined aquifer at approximately 120 m depth. The data demonstrate strong correlation with existing borehole logs, indicating groundwater occurrence at depths up to 120 m, with some boreholes reaching 100 m. The findings suggest significant potential for sustainable groundwater exploitation to support socio-economic development in the area.