Indirect estimation of electrical resistivity by abrasion and physico-mechanical properties of rocks

Abstract

This paper attempts to estimate electrical resistivity from physico-mechanical and abrasion properties of rocks. For this purpose, the electrical properties of rock samples collected from igneous and metamorphic formations were initially measured in a laboratory by employing the two-electrode method. In addition, physical, mechanical, and abrasion properties of the rocks were determined. Then, an attempt was made to examine the possibility of estimation of electrical resistivity from other rock properties.In this sense, it was found that water content, porosity, and the ratio of Vp/Vs have significant effects on the electrical resistivity. Moreover, we report that indirect tensile strength and static elastic modulus indirectly control the electrical characteristics of rocks, since reasonable correlations exist between them. Nevertheless, the reliability of the effect of rock abrasion on the resistivity could not be confirmed with a high degree of certainty. More data are needed to check its validity. Thus, we conclude in light of statistical analyses that the results of the tests and the relationships are statistically significant. For this reason, the electrical resistivity of the intact rock can be indirectly estimated by accounting for the physico-mechanical properties for a given formation. However, rock abrasion cannot be considered for the same purpose.