Fabrication of resistivity meter and its evaluation within shallow depth of investigation

The high cost of imported and popular resistivity meters has led many geoscientists, geophysical companies and tertiary institutions to go for locally fabricated resistivity meters. These demands and interests in the locally made resistivity meters inspired the authors for solution by designing and fabricating a resistivity meter with voltage and current output. For its evaluation and comparison, the fabricated resistivity meter and ABEM SAS 300 terrameter were used to carry out the same investigations at the same locations in different parts of Nigeria. The investigations carried out involved horizontal profiling (HP), using Wenner configuration and vertical electrical sounding (VES), using Schlumberger configuration. The results obtained are presented as tables, graphs and sounding curves. The RMS errors of the sounding curves generated from VES, range from 2.5 to 4.1. The comparison of the field data obtained from both meters showed good correlation.