Geophysical mapping involving VLF Electromagnetic profiling along seven profiles, ten Offset Wenner\nand two azimuthal soundings were employed in the study of perennial spring sites at Iloyin community\nin Akure metropolis, southwest Nigeria. Geophysical methods are useful in mapping areas of natural\nwater resource for groundwater abstraction or construction of containment such as dam or fishpond.\nLinear inversion of the Electromagnetic measurements involved application of the Fraser and Karous-\nHjelt filter on the measured real components of the field data and generation of pseudo sections. The\nazimuthal sounding data were presented as azimuthal graphs in both Cartesian and Polar coordinates\nin conjunction with the polar plots of the Offset Wenner resistances (RD1 and RD2). The topsoil is\ngenerally thin with resistivity values ranging between 65 to 612 Ohm-m and thickness from 0.5 to 2.9 m.\nThe underlying layer with resistivity value ranging from 25 to 468 ohm-m is the main aquifer recognized\nas quartzite bed and quartzite impregnated clayey aquifer. The Aquifer layer thickness varies between\n0.9 to 32.6 m. The basement rocks, which graduate from highly weathered/fractured to fresh bedrocks,\nare characterized by resistivity values ranging from 827 to 11064 Ohm-m. Aquifer units in the area\ncomprise brecciated quartzite, clayey sand and fractured bedrock. The topsoil is highly loose and\nunprotected which makes the aquifer in the study area susceptible to infiltration and groundwater being\nprone to pollution.
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