Abstract:
Geophysical studies have been undertaken at the undeveloped southwestern flank of the
Federal University of Technology Akure. The area is underlain by the Precambrian Crystalline
Basement complex rocks. Six traverses were established in approximately W-E and N-S
directions with lengths varying from 440 to 600 m. The methods adopted are the ground
magnetic, electromagnetic (VLF-EM) and electrical resistivity using dipole-dipole profiling
and Vertical Electrical Sounding (VES) technique. The acquired field data’s were processed
using 2D Euler Deconvolution, Karous Hjelt, Diprowin and WinRESIST respectively.
Geologic structures were delineated from sections generated from the methods adopted. The
integrated results of the, magnetic, EM-VLF and electrical resistivity using dipole-dipole
profiling guided the choice of thirty five (35) VES stations occupied within the study area. The
VES results delineated three geoelectric layers overlying the resistive basement, comprising
the topsoil, weathered layer and partially weathered/fractured basement. The depth to the top
of the basement (overburden thickness) varies from 3.2 to 69.2 m. On the basis of the
combination of the results of geomagnetic depth column, VLF-EM 2-D model, 2-D resistivity
structures and geoelectric sections along the six traverses, some features presumed favorable
to ground water accumulation were identified. Traverses 1 and 2 show existence of probable
geologic features between station 180 and 300 m, suspected to be fractures that may facilitate
location of groundwater abstraction facilities. Results obtained along traverses 3 and 4 depict
some conspicuous anomalies on the southern flank at station 40, 160, and 300 m. Some level
of correlation exist among the subsurface models depicted by the geophysical methods along
traverses 5 and 6. The features identified at station 160 and 350 m west of traverse 5 were
delineated on traverse 6 between station 130 and 400 m thus, indicating the presence of
fractures, fluid saturation media and other hydrogeological related features. Therefore, the
hydrogeological settings within the study area present fairly favorable characteristics.
