RBSR AND SM-ND ISOTOPIC SYSTEMATICS OF THE GRANITOIDS AND ORES OF THEVOSTOK-2 SCHEELITE DEPOSIT, PRIMORIE

The Vostok-2 deposit is situated in granodiorites of the Central Stock , which intrudes Permian sandy-carbonate rocks. A large granitoid mass if known as Dal'ninskii is located south of the deposit. Based upon Rb -Sr datings, the age of the Dal'ninskii massif is 103 +/- 1 Ma, and th at of the Central stock is 101 +/- 1 Ma. The Rb-Sr age of greisenizati on and ore formation agrees within the error level with that of the Ce ntral stock. Sm-Nd and Rb-Sr isotope data indicate that the granitoids of the Dal'ninskii Massif and the Central stock originated through th e influx of mantle melts or fluids into the continental crust. The con tribution of mantle-derived Nd and Sr in the granitoid melt may amount to up to 70-80% for the Dal'ninskii massif and 50% for the Central st ock. The greisens and ores were derived mainly by fluids from the magm atic source of the Central stock granitoids. A contribution from this source to the mineralizing fluid accounted for 85%; the remaining 15% were derived from the host sandstone.