Authors

Abstract

Electrical Resistivity Imaging (ERI) method is one of the most promising
techniques which is well suited for the applications in the fields of geohydrology,
environmental science and engineering. The present work is aimed to show the
efficiency of 2D Electrical Resistivity Imaging (ERI) and Induced Polarization (IP) in
probing the subsurface soil for site investigation and differentiating the clayey soil
layers as it is a common practice to measure the IP sounding along with resistivity for
correct interpretation of field data. The study has demonstrated the practical
application of 2D ERI and IP tomography along 7 lines using Wenner- Schlumberger
array. The data analysis comprises of 2D inversions using the RES2DINV software,
thus 2D electrical resistivity and IP imaging sections have been obtained. The depth of
investigation was 4 m, and resistivity values range from electrical layers were recognized: the upper layer with high resistivity (7-71 ohm.m)
represents the loamy soil extends to a depth around 1.3 m; and the second layer with
low resistivity ( high electric zones are appeared reflecting the inhomogeneity in deposits. The IP
values are ranging from -2 to 17 mV/V showing good confirmation with resistivity
data, where high chargeability are associated with low resistivity. The study reveals
that combining IP with resistivity surveys is recommended since IP is, sometimes, very
effective in relieving ambiguity in interpretation.

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