PGE Prospecting Features by Results of SP and Geoelectrochemistry Methods

Platinum-group elements (PGE) prospecting can be carried out with use of geochemical or geophysical methods. Geochemical methods can study objects located at the surface only, and geophysical methods are not always effective because of too low concentrations of PGE in the host rocks do not change the ores physical properties. Geoelectrochemical methods are suitable for deep-lying ores prospecting. Problem of movable forms creation of passive PGE can be fixed takin into account natural electrical processes. It is shown by laboratory experiment and tested during field works. Laboratory data confirmed the influence of electric current on the transition of PGE dozens presents in the dissolved form. The complex geophysical and geoelectrochemical surveys was carried out on the territory of Aganozerskiy (South Karelia), Svetloborskiy and Kachkanar (Middle Urals) massifs containing PGE mineralization. Preconditions for the creation of self-potential (SP) anomalies of redox nature are allocated within these massifs and characteristics of self-potential anomalies are investigated. SP sources are prerequisite for the mobile PGE forms halos creation if they are close to platinum mineralization zones. Moving up in the jet halos by natural ionic flotation mechanism and capillary rise in a circle of meteoric water evaporation and seepage can form zones of elevated concentrations of PGE secondary fixed forms near the surface, which can be detected by different geoelectrochemical methods. It can be concluded that geoelectrochemical methods are not always effective, but in the presence of sources of SP in a geological environment. The interpretation of the geoelectrochemistry anomaly for noble metals should take into account the effect of activators of the mobile forms formation.