Sources and thermo-chemical sulfate reduction for reduced sulfur in the hydrothermal fluids, southeastern SYG Pb-Zn Metallogenic Province, SW China

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• 作者：Jiaxi Zhou a> (1)
  Zhilong Huang ∥a> (1)
  Guangping Bao (1)
  Jianguo Gao (2)
  
• 关键词：sulfur isotope ; hydrothermal fluid ; TSR ; southeastern SYG province ; SW China
• 刊名：Journal of Earth Science
• 出版年：2013
• 出版时间：October 2013
• 年：2013
• 卷：24
• 期：5
• 页码：759-771
• 全文大小：
• 作者单位：Jiaxi Zhou a> (1)
  Zhilong Huang ∥a> (1)
  Guangping Bao (1)
  Jianguo Gao (2)
  
  1. State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550002, China
  2. Faculty of Land Resource Engineering, Kunming University of Science and Technology, Kunming, 650093, China
  
• ISSN：1867-111X

文摘

Located on the western Yangtze Block, the Sichuan (-Yunnan()-Guizhou( (SYG) Pb-Zn metallogenic province has been a major source of base metals for China. In the southeastern SYG province, structures are well developed and strictly control about 100 Pb-Zn deposits. Almost all the deposits are hosted in Devonian to Permian carbonate rocks. Lead-zinc ores occur either as veinlets or disseminations in dolomitic rocks with massive and disseminated textures. Ore minerals are composed of pyrite, sphalerite and galena, and gangue minerals are calcite and dolomite. Sulfide minerals from four typical Pb-Zn deposits are analyzed for sulfur isotope compositions to trace the origin and evolution of hydrothermal fluids. The results show that 4S values of sulfide minerals range from +3.50to +20.26 with a broad peak in +10to +16 unlike mantle-derived sulfur (0 However, the mean 4Ssulfide and 4S-fluids values are similar to that of sulfate-bearing evaporites in the host rocks (gypsum: +15and barite: +22to +28 and Cambrian to Permian seawater sulfate (+15to +35. This suggests that reduced sulfur in hydrothermal fluids was likely derived from evaporates in the host rocks by thermo-chemical sulfate reduction (TSR). Calculated 4S-fluids values of the Shanshulin(V), Qingshan(), Shaojiwan() and Tianqiao() Pb-Zn deposits are +21.59 +18.33 +11.43and +10.62 respectively, indicating sulfur-bearing hydrothermal fluids may be evolved from the Shanshulin to Qingshan and then the Shaojiwan to Tianqiao deposition sites along the Yadu(-Ziyun() lithospheric fracture in the southeastern SYG province.