中文摘要:厅宫斑岩铜矿床是西藏冈底斯斑岩铜矿带上重要的矿床之一。为了探明该矿床成矿流体的成分及温压条件等物理化学性质,文章对厅宫铜矿各蚀变阶段石英脉及石英斑晶中的流体包裹体进行了显微测温、四极杆质谱、离子色谱和激光拉曼探针分析,结果表明:厅宫铜矿成矿流体为高温、高盐度岩浆热液,成矿事件主要发生在340~380℃,成矿过程中流体发生了沸腾;成矿流体中气相成分以H2O为主,还含有一定量的CO2及少量的CH4、H2S、C2H6等气体;液相中离子以K+、Na+、Cl-、SO2-4、F-等为主,还含有少量的Ca2+、Mg2+等;另外,出现大量气泡先消失、子矿物后熔融的Ⅲa类包裹体,表明有些成矿流体可能直接来源于深部岩浆的出溶作用。
Abstract:The Tinggong porphyry copper deposit (PCD) is an important deposit in Gangdese PCD belt. According to a detailed study of quartz veins and quartz phenocrysts, the ore_forming fluids of the Tinggong deposit might have been derived from magmatic fluids characterized by high temperature and high salinity. Boiling, as shown by coexisting liquid_rich and vapor_rich inclusions with similar homogenization temperatures, must have happened during the ore_forming process, with the copper precipitation occurring in the temperature range of 340℃ to 380℃. Laser Raman Microprobe Analysis (LRM), Quadrupole Mass Spectrum Analysis (QMS) and Ion Chromatography Analysis (IC) were performed for fluid inclusions from the Tinggong PCD. It can be concluded from the above results that the ore_forming fluids are rich in Na+, K+, Ca2+, F-, Cl- and SO2-4 as well as small amounts of CO2, H2S and CH4. Ore_forming fluids probably partly originated from deep magma exsolution, as evidenced by the existence of Ⅲa_type inclusions.
keywords:geochemistry, fluid inclusion, exsolution, porphyry copper deposit, Tinggong, Gangdese, Tibet
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基金项目:国家自然科学基金(编号:40272047)和国家基础研究规划973项目(编号:2002CB412600)
引用文本:
杨志明,谢玉玲,李光明,徐九华,王葆华.2005.西藏冈底斯斑岩铜矿带厅宫铜矿床流体包裹体研究[J].矿床地质,24(6):584~594.2005.Study of fluid inclusions from Tinggong porphyry copper deposit in Gangdese belt, Tibet [J].Mineral Deposits24(6):584~594
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