SHUANG Yan1,2, FU Shao-hong3, ZHU Zheng-jie1,2, GONG Kui1,2, XIANG Yu1,2, MAO Ling-ling1,2
(1. Chongqing Key Laboratory of Exogenic Minerallization and Mine Environment,Chongqing Institute of Geology and Mineral Resources, Chongqing 400042, China;
2. Chongqing Research Center of State Key Laboratory of Coal Resources and Safe Mining, Chongqing 400042, China;>
3. State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China)
Abstract: The Shidi lead-zinc deposit is located in Xiushan county in southeast Chongqing. Its orebodies occur in marine carbonates of the Cambrian Pingjing formation. The authors selected sulfide minerals from the deposit for sulfur and lead isotope compositional analyses. The δ34S values of these sulfide minerals vary from 10.8% to 15.6% and show an average value of 13.52%, indicating the sulfur was mainly derived from marine sulfate reduction and reduced sulfurs that were probably derived from thermo-chemical sulfate reduction. The 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb ratios for these sulfide minerals vary, ranging from 18.319 to 18.422, 15.740 to 15.784 and 38.355 to 38.511 respectively. The Zartman diagrams show the Pb isotope compositions of these sulfide minerals fall into the regional upper crustal lead zone. In the Δβ-Δγ diagram values fall into the upper crustal lead zone implying that Pb might have come from rocks in the upper crust. According to the geochemical characteristics of the sulfur and lead isotope compositions from the Shidi Pb-Zn deposit, the ore-forming materials might have come from the black shale of the Lower Cambrian Niutitang Formation.
Key words: Shidi Pb-Zn deposit; lead isotope; sulfur isotope; sources of ore-forming material
ACTA MINERALOGICA SINICA Vol. 34, No. 4, 2014, Page 496-502
