AGE AND ISOTOPIC CHARACTERISTICS OF THE BULUKTAI MO-W DEPOSIT (REPUBLIC OF BURYATIA)

The purpose of the article is to date the ore formation process, study the composition and provide the description of mineral parageneses in rocks and ores of the Buluktai Mo-W deposit as well as to estimate the sources of matter and fluids. The Re-Os method (The Center for isotopic studies of A.P. Karpinsky Russian Geological Research Institute (VSEGEI)) is used for dating the molybdenum mineralization. The isotopic compositions of oxygen in silicates and carbon in carbonates is determined in the Geological Institute SB RAS. The isotopic composition of hydrogen of muscovite hydroxyl water is determined in the Center for isotopic studies of the Far Eastern Branch RAS. The isotopic analysis of sulfide sulfur is carried out in the Center for isotopic studies of the Far Eastern Branch RAS and partly at the Tbilisi State University. The age of the molybdenite phase (144±10 Ma) has been determined using the Re-Os method. The isotopic compositions of sulfide sulfur in both molybdenum and tungsten stages show a range of values close to the values of a mantle source. The isotopic compositions of oxygen in the minerals of Mo and W-stages are clearly divided into two groups. The deposit was formed with the participation of a mantle source. Its final stage is characterized with the increased influence of meteoric water as a part of fluids.

Re-Os анализ, Mo-W deposit, quartz-hubnerite-scheelite veins, beryl, molybdenite, isotopic composition of oxygen, sulfur, hydrogen, and carbon, Re-Os analysis

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