The small-scale Balugou Cu-Pb-Zn skarn deposit(45 298 tonnages of ore at 0.1% to 3.99% Cu, 0.20% to 0.43% Pb and 0.76% to 10.92% Zn) is located in the Wulonggou area in the eastern Kunlun orogen, NW China. Ore depos...The small-scale Balugou Cu-Pb-Zn skarn deposit(45 298 tonnages of ore at 0.1% to 3.99% Cu, 0.20% to 0.43% Pb and 0.76% to 10.92% Zn) is located in the Wulonggou area in the eastern Kunlun orogen, NW China. Ore deposition is spatially and temporally related with the pre-collisional Anisian Balugou granites(~244 Ma). The mineralization hosted by the contact between marble beds within the Paleo-Proterozoic Jinshuikou Group and Balugou granites, was structurally and lithologically controlled. The mineralogy of the Balugou deposit includes an early simple skarn mineral gangue(epidote with little diopside) and a late complicated quartz sulfide assemblage(pyrite, pyrrhotite, chalcopyrite, sphalerite, galena, bornite, quartz, carbonate and chlorite). The δ34S values of eighteen sulfides range from-2.1‰ to +2.8 ‰, with an average of +0.07‰, and the calculated δ34SH2S values for H2 S in hydrothermal fluids range from-3.2‰ to +2.4‰, with an average of +0.03‰, suggesting a relatively homogeneous magmatic(±mantle) source, with sulfur produced directly by the Balugou granites. The sixteen sulfides have 206Pb/204 Pb ratios from 18.367 4 to 18.384 1, 207Pb/204 Pb ratios from 15.634 6 to 15.641 5, and 208Pb/204 Pb ratios from 38.455 5 to 38.485 0, which are close to those of K-feldspars from the Balugou granites, but are far away from age-corrected lead isotopic ratios of six wall-rock samples. So it was considered that the Pb sources of sulfides must be almost derived from the Balugou granites rather than the older wall-rocks. Collectively, it's suggested that the Balugou Cu-Pb-Zn deposit belongs to skarn deposit, and the sulfur and lead deposited in it were leached from the Anisian Balugou granites.展开更多
基金supported by the National Natural Science Foundation of China(Nos.41572056 and 40802021)the Open Foundation from the State Key Laboratory for Mineral Deposits Research,Department of Earth Sciences in Nanjing University(No.17-1112-4)
文摘The small-scale Balugou Cu-Pb-Zn skarn deposit(45 298 tonnages of ore at 0.1% to 3.99% Cu, 0.20% to 0.43% Pb and 0.76% to 10.92% Zn) is located in the Wulonggou area in the eastern Kunlun orogen, NW China. Ore deposition is spatially and temporally related with the pre-collisional Anisian Balugou granites(~244 Ma). The mineralization hosted by the contact between marble beds within the Paleo-Proterozoic Jinshuikou Group and Balugou granites, was structurally and lithologically controlled. The mineralogy of the Balugou deposit includes an early simple skarn mineral gangue(epidote with little diopside) and a late complicated quartz sulfide assemblage(pyrite, pyrrhotite, chalcopyrite, sphalerite, galena, bornite, quartz, carbonate and chlorite). The δ34S values of eighteen sulfides range from-2.1‰ to +2.8 ‰, with an average of +0.07‰, and the calculated δ34SH2S values for H2 S in hydrothermal fluids range from-3.2‰ to +2.4‰, with an average of +0.03‰, suggesting a relatively homogeneous magmatic(±mantle) source, with sulfur produced directly by the Balugou granites. The sixteen sulfides have 206Pb/204 Pb ratios from 18.367 4 to 18.384 1, 207Pb/204 Pb ratios from 15.634 6 to 15.641 5, and 208Pb/204 Pb ratios from 38.455 5 to 38.485 0, which are close to those of K-feldspars from the Balugou granites, but are far away from age-corrected lead isotopic ratios of six wall-rock samples. So it was considered that the Pb sources of sulfides must be almost derived from the Balugou granites rather than the older wall-rocks. Collectively, it's suggested that the Balugou Cu-Pb-Zn deposit belongs to skarn deposit, and the sulfur and lead deposited in it were leached from the Anisian Balugou granites.