Electical properties of some Ghanaian metamorphic rocks.

Abstract

The temperature dependence of electrical resistivity of three Ghanaian metamorphic rocks has been investigated between room temperature (300K) and 570K. The resistivity values were measured for samples prepared in directions parallel and perpendicular to the rock foliation. The resistivity behaviour was found to be highly anisotropic and the anisotropic coefficients were found to be between 3.0 and 7.0. All the rocks showed a transition at a characteristic temperature where the resistivity became a maximum beyond which it decayed exponentially. The activation energy calculated for some temperature ranges was found to be of the order of 1 eV (10-19J) which is typical of semiconductor behaviour within these regions.