Iron redistribution during postore stage at uranium deposits of the Khiagda ore field, Vitim district

The localization conditions of mineralization at uranium deposits of the Khiagda ore field related to the economic sandstone type in paleovalleys are considered in this paper. These conditions allow different genetic treatments. Uncertainty in genetic estimates is caused by localization of orebodies in both gray sedimentary rocks at the boundary with bleached rocks and in the bleached rocks themselves. The results of mineralogical and geochemical studies have shown that bleaching is related to iron redistribution at the postore stage. Obvious evidence in favor of this conclusion has been obtained from statistical processing of quantitative soluble iron determinations in various geochemical types of host rocks. The postore bleaching is superposed on earlier oxidized and ore-bearing gray rocks, obliterating the coloration inherent to redox ore-controlling zoning.