Metamorphism and granitization in the formation of the gold deposit Jeruy, Kyrgyzstan

摘要

Results of lithological, petrographic and geochemical studies of the Jeruy gold deposit, Talas Ridge, Kyrgyzstan are presented. The deposit is being prepared for exploitation in a joint venture between the mining companies Normandy and Oxus. Gold mineralisation in the granitoid massif was formed mainly by metamorphism, granitisation and hydrothermal reworking of primary gold-bearing carbonates (R_2). The metamorphic sequence of schists, gneisses and marbles contain quartz veins, lenses, and lodes with gold grades up to 0.7 g/t. Subsequent granitization of this sequence, emplacement of granites, granodiorites, diorites, and hybrid rocks, and, at in the final stage, post-magmatic processes, led to concentration of economic gold-quartz mineralisation. Patterns of localisation and formation of mineralization at Jeruy were confirmed by the latest exploration efforts and helped to increase the gold reserves in the ore field and in the district as a whole.