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In basement complex terrains, groundwater potential is controlled principally by the subsurface structures and thickness of
the overburden. The applicability of the magnetic method in mapping geologic structures vis-à-vis delineation of fault /
fracture zones and rock contacts as well as estimation of their depths beneath Obanla area of Federal University of
Technology, Akure is addressed in this paper. The magnetic data were acquired along five traverses namely; TR1, TR2,
TR3, TR4 and TR5 established in a NW - SE direction. The analyses made on the diurnal corrected ground magnetic data
acquired from the area includes Upward Continuation, Vertical / Horizontal Derivative and Analytical Signal computed in
the wave number domain. The anomaly patterns identified in the upward continued map are used to outline the study area
into distinct structural zones. The north western and south western region with maximum magnetic intensity values
(33660nT – 33980nT) possibly suggest shallow basement (i.e. thin overburden thickness) while the eastern region
characterized by relatively low magnetic anomaly amplitude (33500nT – 33380nT) indicates a relatively deep source (thick
overburden). The derivative maps and analytic signal map delineated fault and / or fracture zones and rock contacts
respectively in the area. For the quantitative interpretation, Euler deconvolution technique was utilized to estimate depths to
magnetic sources in the area i.e. 10 – 50m. The results of this study could serve as a guide for future groundwater prospect in
the area using electrical survey.
Key words: Groundwater potential, magnetic, Euler deconvolution, fault, analytic signal.