投稿时间:2017-10-20
修订日期:2018-02-08
网络发布日期:2018-04-25
中文摘要:崤山金矿床位于华北克拉通南缘的豫西地区,矿体大多呈脉状产于断裂带内。成矿期可以划分为3个阶段:①石英-黄铁矿阶段;②石英-多金属硫化物阶段;③石英-碳酸盐阶段。成矿期石英中发育气液两相水溶液包裹体(WL型)和H2O-CO2包裹体(C型)。石英-黄铁矿阶段发育WL型和C型包裹体,它们的均一温度为300~393℃,盐度w(NaCleq)为1.6%~11.0%,密度介于0.57~0.82 g/cm3;石英-多金属硫化物阶段亦发育WL型和C型包裹体,它们的均一温度为261~298℃,盐度w(NaCleq)为1.1%~11.8%,密度介于0.74~0.89 g/cm3;石英-碳酸盐阶段仅见WL型包裹体,其均一温度为193~258℃,盐度w(NaCleq)介于2.2%~12.7%,密度为0.87~0.97 g/cm3。成矿流体具有中高温、中低盐度、低密度等特征,属于H2O-NaCl±CO2体系。崤山金矿石英的δ18OH2O值介于0.7‰~4.5‰之间,δDV-SMOW值介于-47.8‰~-69.5‰之间。H-O同位素结果表明成矿流体主要来源于岩浆水。矿石硫化物的δ34SV-CDT值为0.7‰~3.9‰,206Pb/204Pb值为17.391~17.728,207Pb/204Pb值为15.420~15.577,207Pb/204Pb值为37.420~37.923。S-Pb同位素结果表明成矿物质主要来源于花岗质岩浆。崤山金矿为中温热液脉型金矿,流体相分离和温度的降低是导致矿质沉淀的主要机制。
Abstract:The Xiaoshan gold deposit is located on the southern margin of the North China craton in western Henan Province. Orebodies occur as veins in the fault zones. The ore-forming process can be divided into three stages:The early quartz-pyrite stage, the middle quartz-polymetallic sulfide stage, and the late quartz-carbonate stage. Two types of fluid inclusions (FIs) were distinguished in various quartz veins, i.e., liquid-rich (WL type) and H2O-CO2 (C-type) inclusions. The fluid inclusions in the quartz of the quartz-pyrite stage comprise WL-and C-type inclusions; their homogenization temperatures, salinities w(NaCleq), and densities vary from 300 to 393℃, 0.57% to 0.82%, and 1.6 to 11.0 g/cm3, respectively. The fluid inclusions in the quartz of the quartz-polymetallic sulfide stage consist of WL-and C-type inclusions; their homogenization temperatures, salinities w(NaCleq), and densities range from 261 to 298℃, 1.1% to 11.8%, and 0.74 to 0.89 g/cm3, respectively. There are only WL-type inclusions in the quartz of the quartz-carbonate stage; their homogenization temperatures, salinities w(NaCleq), and densities vary from 193 to 258℃, 2.2% to 12.7%, and 0.87 to 0.97 g/cm3, respectively. The ore-forming fluids of the Xiaoshan gold deposit are generally characterized by moderate-high temperature, moderate-low salinity, and low density, thus belonging to the H2O-NaCl±CO2 system. The δ18OH2O values calculated for ore-bearing quartz vary from 0.7‰ to 4.5‰, and the δDV-SMOW values from bulk extraction of fluid inclusion water vary from -47.8‰ to -69.5‰, suggesting that the ore-forming fluids consist dominantly of magmatic water. The δ34SV-CDT values range from 0.37‰ to 3.9‰. The 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb ratios of the ore minerals are in the ranges of 17.391~17.728, 15.420~15.577, and 37.420~37.923, respectively. The data from the S and Pb isotopic systems indicate that the ore-forming materials came from the granitic magma. The Xiaoshan gold deposit is a mesothermal vein-type gold deposit. Fluid phase separation and temperature decrease seem to have been the dominant mechanism for the deposition of ore-forming materials.
keywords:geochemical fluid inclusions H-O-S-Pb isotopes Xiaoshan gold deposit western Henan Province southern margin of the North China Craton
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基金项目:中国地质调查局地质调查项目(编号:12120114035201)和中国地质调查局中国矿产地质与成矿规律综合集成和服务(矿产地质志)项目(编号:DD20160346)资助
引用文本:
李铁刚,孟宪锋,王国瑞,肖建辉,吴昊,范海洋,员晓琪.2018.河南崤山金矿床流体包裹体及同位素特征[J].矿床地质,37(2):403~419LI TieGang,MENG XianFeng,WANG GuoRui,XIAO JianHui,WU Hao,FAN HaiYang,YUAN XiaoQi.2018.Fluid inclusions and isotopic characteristics of Xiaoshan gold deposit in Henan Province[J].Mineral Deposits37(2):403~419
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