BIOGENIC CONCENTRATION OF GOLD IN THE GOLDFIELDS OF THE GOLETS ZONE

Abstract

The golets zone in the mountains of southern Siberia occupies the summit belt of upland regions. Golets plants are enriched in many trace elements; the coefficient of biologic absorption, as calculated to the clarke for the lithosphere, exceeds unity (Table 1). Lichens are moderate gold accumulators, although in goldore zones their gold content increases sharply. Biogenic gold concentration was studied in gold-quartz and gold-sulfid shows. Gold-quartz veins are controlled by fault zones in Precambrian and Paleozoic granites. Gold-sulfide mineralization is associated with black and green shale horizons in Riphean and Paleozoic volcanogenic-clastic complexes, as well as in Vendian ophiolites. Biogeochemical gold anomalies on floors of glacial cirques and at the foot of block-stream slopes are related to suffosional and aqueous dispersion halos of gold-quartz vein zones. On floors of U-shaped valleys, peat bogs are developed in swampy lows, silt-filled impounded basins in front of riegels and moraine ridges. Additional aspects of the subject are discussed.