矿床地质2017，Vol.36Issue(3)：623-642,20.DOI:10.16111/j.0258-7106.2017.03.006
湘西花垣李梅铅锌矿床C、O、S、Pb同位素特征及成矿物质来源
C, O, S and Pb isotopic characteristics and sources of metallogenic materials of Limei Pb-Zn deposit in Huayuan County, western Hunan Province
摘要
Abstract
The Limei Pb-Zn deposit located on the southeastern margin of the Yangtze block,is one of the earlier-discovered and giant Pb-Zn deposit occurring in bedded and stratoid forms and hosted by lower Cambrian algal limestone in the Huayuan orefiled of the Xiangxi-Exi metallogenic belt.C,O,S and Pb isotope geochemistry was analyzed in this paper in order to understand comprehensively the source and evolution of the metallogenic matcrial and the ore fluids.The results show that δ13CpDB values of the ore-stage hydrothermal calcites are-2.79 ‰～1.11‰,and δ18OsMoW are 14.59‰～23.05‰,indicating that the CO2 in the ore-forming fluid was derived from the dissolution of Cambrian carbonates,whereas the post ore-stage and parts of ore-stage hydrothermal calcites should be related to the thermochemical reduction rcaction of the organic matter.The laser Raman spectroscopy shows that the gas components have large quantities of CH4,H2S,N2 and other hydrocarbons,and the authors thus infer that the organic matter at high mature stage of evolution was involved in mineralization in the formof oil-gas field.The presence of gas bituminiferous inclusions in sphalerite suggests that the thermochemical reduction reaction was involved in mineralization.The δ34SCDT values of sulfides are + 26.30‰～ + 34.66‰,suggesting that the sulfur must have been derived from the fully thermochemical reduction reaction of sulfates from the ore-forming brine.The 206Pb/204pb,207pb/204pb and 208pb/204pb values for thc ores vary in the range of 17.999～ 18.235,15.584～ 15.789,and 38.147～ 38.576 respectively,implying that the metallogenic material was most likely derived from the Proterozoic low metamorphic basement and the lower Cambrian Niutitang Formation black shale,with part of the ore metals from the host algal limestone.关键词
地球化学/同位素/成矿物质/成矿流体/李梅铅锌矿床Key words
geochemistry/isotope/metallogenic materials/ore fluids/Limei Pb-Zn deposit分类
天文与地球科学引用本文复制引用
胡太平,王敏芳,丁振举,何谋惷,王彦博,郭晓南..湘西花垣李梅铅锌矿床C、O、S、Pb同位素特征及成矿物质来源[J].矿床地质,2017,36(3):623-642,20.基金项目
本研究得到中国地质调查局项目(编号:12120114016601)、国家自然科学基金面上项目(编号:41272097)、中央高校基本科研业务费专项资金(编号:CUG120702)和中国地质大学(武汉)教学实验室开放基金项目(编号:SKJ2014010)的联合资助 （编号:12120114016601）
