The Use of a Predictive Statistical Technique in Geo-Electrical Investigations

Abstract

The method of simple regression analysis was employed to test for the correlation at the various depths of investigation between AB/2 and resistivity for the geoelectrical data collected from six VES points (i.e. A1 – A6). The VES dataset had been interpreted in the usual manner to obtain information about number of layers, their thicknesses, and depth to basement along the profile on which soundings were carried out. Having applied the method of regression analysis to for (i) maximum AB/2 = 100m, (ii) maximum AB/2=40m, it was found that the values of the standard error of estimates are within tolerable limits for VES points A1, A2, A3, and A4 (i.e. about 67% correlation). Thus it was recommended that between VES points A1 and A6, intermediate VES points (say 50m spacing) could be sounded with savings in time and cost. Now, instead of fourteen sounding sequences that are concerned with depth to basement, just the first six sequences could be sounded and the remaining dataset can be extrapolated to AB/2 = 40m.