Rhenium in molybdenites from porphyry Cu-Mo deposits of Russia (Siberia) and Mongolia

The rhenium content was determined in representative molybdenite samples (concentrates) from the Aksug, Erdenetuin-Obo, Zhireken, Shakhtama and Sora Cu-Mo deposits of Russia (Siberia) and Mongolia. The Aksug and Erdenetuin-Obo deposits with relatively elevated Re content (up to 460 ppm) differ from the Zhireken, Shakhtama and Sora deposits with lower Re contents (a few decades ppm) in terms of: (1) their higher values of the Cu/Mo ratio; (2) the lower values of the delta(34)S and Sr-87/Sr-86 isotopes; (3) the alteration type of the associated rocks, (4) the elevated Cl activity in the fluid; (5) the lower temperature of the molybdenite formation, (6) the lower depth of the deposit formation, and (7) the higher oxidized conditions. Major controlling factors of the Re contents in molybdenites from porphyry Cu+/-Mo deposits may be the composition of parent magmas, the depth of the ore formation and variations of fO(2), P, T conditions.