ABSTRACT
2D magnetotelluric surveying is becoming common in Nigeria for groundwater exploration, this because the equipment is cheaper compared to other geophysical tools and also very easy to use in terms of field application. The results are presented in 2D inversions making it relatively easy to interpret in terms of electrical distribution and variation within the subsurface. 10 profiles of magnetotelluric data were conducted in Tangur and environs which is basically a basement terrain with the aim of delineating areas for groundwater exploration. Tangur falls under the Sha-Kaleri complex whose geology includes: granite Gneiss, biotite granite, basalt and diorite dike. The geologic structures include: fractures, mafic rich mineral dikes and mafic enclaves. The profile results show that the study area has good groundwater potentials. The resistivity values of potential areas for groundwater exploration in Tangur from 2D magnetotelluric profiles are 115 – 215 Ωm, 130 – 205 Ωm, 123 – 245 Ωm, 35 – 125 Ωm, 90 – 240 Ωm and 155 – 245 Ωm while the depths for drilling of boreholes are recommended to be 60 – 80 m, 0 – 80 m, 60 – 80 m, 180 – 200 m and 180 – 200m respectively, these are based on the location of the profiles.
Key words: 2D Inversion, Groundwater, Magnetotelluric, Borehole and Basement
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