Vol. 13 No. 2 (1973)
Articles

ELECTRODE EFFECTS AND ELECTRICAL NON-LINEAR BEHAVIOR IN ROCKS

Roman Alvarez
Instituto de Geofísica, Universidad Nacional Autónoma de México.

Published 1973-04-01

How to Cite

Alvarez, R. (1973). ELECTRODE EFFECTS AND ELECTRICAL NON-LINEAR BEHAVIOR IN ROCKS. Geofísica Internacional, 13(2), 161-185. https://doi.org/10.22201/igeof.00167169p.1973.13.2.1002

Abstract

Previous studies on rocks saturated with electrolyte have shown electrical linear behavior up to a current density limit; above such a limit non-linearities appear. Evidence was obtained of the opposite behavior in some "dry" resistive rocks in contact with metallic electrodes. It shows the existence of a non-linear region followed by a linear one when the voltage, or current density, is increased. Experimental evidence of charge concentrations in the metallic electrodes’ vicinity is related to non-linear phenomena at low voltages. A conduction model based on transient responses of a hernatitic sandstone-In Hg system identiï¬es two groups of charge carriers. One group is characterized by a fast relaxation mechanism that appears to be associated with surface conduction, the other is associated with low-mobility carriers apparently moving through the rock matrix.