PROSPECTING FOR NON‐METALLIC MINERALS BY INDUCED POLARIZATION*

Abstract

ABSTRACT The method of induced polarization finds more and more application in the prospection of metallic ore deposits. It is very useful also in the determination of non‐metallic minerals and underground water flows. In the case when an electrical current flows accross the interface between metallic and electrolytic phases the causes of the induced polarization are well known and have often been discussed. In the case of non‐metallic minerals and rocks the polarization is mainly caused by the membrane potential, since the polyelectrolytic clay material, having the capacity of ion‐exchange in micells, acts as a semipermeable membrane. Practical examples of exploration for non‐metallic mineral by the induced polarization method are discussed. Some kaolin deposits have been revealed. The depth and the extent of a clay layer, impervious to water, are determined in the bottom of a future storage lake of an hydroelectric power‐plant. The underground water flows in the Karst region are traced.