投稿时间：2018-10-09
修订日期：2019-02-20
网络发布日期：2019-04-30
中文摘要:四川木里梭罗沟金矿床是产于甘孜-理塘金矿带南端的大型金矿床。矿体产于近东西向断裂控制的构造蚀变带内，矿石类型主要为蚀变蚀变玄武岩矿石、凝灰岩矿石。由深部至浅部，依次发育硅化、黄铁绢英岩化、碳酸盐化蚀变。流体成矿过程包括早、中、晚3个阶段，分别以石英-他形黄铁矿组合、石英-五角十二面体黄铁矿-毒砂组合和石英-碳酸盐±少量立方体黄铁矿组合为标志。矿石矿物主要沉淀于中阶段，五角十二面体黄铁矿和毒砂是主要的载金矿物。早阶段热液石英中发育CO2-H2O型包裹体（C型）和水溶液包裹体（W型），中、晚阶段只发育水溶液包裹体（W型）。早阶段流体包裹体均一温度集中于251~371℃，盐度w（NaCleq）为3.3%~13.7%；中阶段流体包裹体均一温度集中于187~294℃，盐度w（NaCleq）为1.6%~13.9%；晚阶段流体包裹体均一温度集中于144~224℃，盐度w（NaCleq）介于0.2%~10.6%之间。估算的早阶段流体捕获压力为102~343 MPa，推测最大成矿深度为10~11 km。上述流体包裹体研究表明，成矿流体由早阶段中高温、富CO2的变质热液演化至晚阶段的低温、贫CO2的大气降水热液；流体温度降低、CO2逃逸是控制成矿物质沉淀的主要因素。矿床地质及流体包裹体特征指示梭罗沟金矿床可能为断控造山型金矿床。
Abstract:The Suoluogou Au deposit in Muli County of Sichuan Province is a large deposit in the Garze-Litang suture. Au mineralization occurs in the EW-trending fault, and the ores mainly include the altered basalt and tuff. The hydrothermal alteration is intense, ranging from silicification, beresitization to carbonatization with increasing depth. The hydrothermal ore-forming process includes the early, middle and late stages, characterized by mineral assemblages of quartz-allotriomorphic pyrite, quartz-pyritohedron pyrite-arsenopyrite and quartz-carbonate±cubic pyrite, respectively. Ore minerals were mainly precipitated in the middle stage, and the arsenopyrites and pyritohedron pyrites are the main gold-bearing minerals. The hydrothermal minerals in the early stage contain NaClH2O (W-type) and CO2-H2O (C-type) fluid inclusions, while the middle-and late-stage hydrothermal quartz contains only NaCl-H2O fluid inclusions (W-type). The homogeneous temperatures of the C-type and W-type fluid in clusions in the early stage are generally homogenized at temperatures of 251~371℃, with salinities w(NaCleq) of 3.3%~13.7%. In the middle stage, the W-type fluid inclusions mainly have homogeneous temperatures of 187~294℃ and salinities w(NaCleq) of 1.6%~13.9%. W-type fluid inclusions in the late stage are homogenized at temperatures of 144~224℃, with salinities w(NaCleq) of 0.2%~10.6%. The estimated pressures range from 102~343 MPa in the early stage, with the formation depth of 10~11 km. In a word, the ore-forming fluids evolved from middle-high temperature, CO2-bearing metamorphic fluid to low temperature, CO2-poor meteoric fluid. It seems that temperature decreasing and CO2 escaping caused the precipitation of metallogenic materials. The characteristics of the ore geology and fluid inclusions indicated that the Suoluogou Au deposit can be genetically assigned to the orogenic-type ore-system.
文章编号：
中图分类号：P618.51
文献标志码：
基金项目:中国地质调查局地质大地调项目（编号：12120114012501）的资助
引用文本：
杨永飞,刘书生,聂飞,张文林.2019.四川木里梭罗沟金矿床流体包裹体研究及矿床成因[J].矿床地质,38(2):261~276YANG YongFei,LIU ShuSheng,NIE Fei,ZHANG WenLin.2019.Fluid inclusion constraint on origin of Suoluogou Au deposit, Muli County, Sichuan Province[J].Mineral Deposits38(2):261~276
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