C, H, O, S, Pb Isotope Geochemistry and the Implications of Qixiashan Pb-Zn-Ag Polymetallic Deposit in Jiangsu Province

Mingchao Zhang, Yongsheng Li, Xiaofei Yu, Wenbin Jia
2015 Proceedings of the 2015 Asia-Pacific Energy Equipment Engineering Research Conference   unpublished
Qixiashan Pb-Zn-Ag polymetallic deposit in Jiangsu Province is located in the Yangtze continental blockthe Lower Yangtze block zone-central of the Lower Yangtze foreland basin, and is a large polymetallic deposit dominated by Pb and Zn. We have carried out the C and O isotope tests of calcite at the main mineralization stage, H and O isotope tests of quartz at the main mineralization stage, as well as S and Pb isotope analyses and testing of typical sulfide ores in the deposit. The results
more » ... t. The results showed that the δ 13 C V-PDB =-1‰~1.2‰, δ 18 O V-SMOW =14.1‰~21.6‰ of calcite in limestones, δ 13 C V-PDB =-4.9‰~1.9‰, δ 18 O V-SMOW =9.1‰~19.6‰ of calcite in ores. This indicates that carbon largely derived from magma at the main mineralization stage of the deposit, and part of the carbon might come from dissolution of marine carbonate. Quart at main mineralization stage showed δD=-81.8‰~-67‰ and δ 18 O=-0.38‰~6.25‰, indicating that oreforming fluid was mainly magmatic water. And with the progress of mineralization, the mineralization feature of magmatic and meteoric water mixing was revealed. Sulfur isotope ranged in a narrow area from -4.4‰ to 3.6‰ at the main mineralization stage, showing that the main source of sulfur was the magma, and mixed with sedimentary sulfur from the surrounding rocks. The test results for Pb isotopes at main mineralization stage were 206 Pb/ 204 Pb=17.62~17.82, 207 Pb/ 204 Pb=15.51~15.72, 208 Pb/ 204 Pb=37.91~38.59, indicating the lead was not from a single source of the crust or mantle, and it should be a combination of lead from the upper mantle and the crust brought by magmatic activities.
doi:10.2991/ap3er-15.2015.50 fatcat:yl5x6qnqmfaqpkkzh5wxpuzwdu