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锡田垄上锡多金属矿床是湘东锡田锡矿田中的一个大型矿床。通过对锡田垄上矽卡岩型和破碎带蚀变岩型锡多金属矿石中的萤石和石英流体包裹体的岩相学、显微测温分析、包裹体成分的激光拉曼探针分析,结果显示锡田垄上流体包裹体可分为3类5型。3类:盐水包裹体(A类)、富CO2两相包裹体(B类)和含CO2三相包裹体(C类);5型:单相盐水溶液包裹体(A1型)、气液两相盐水溶液包裹体(A2型)、富CO2两相包裹体(B型)、均一成LH2O的含CO2三相包裹体(C1型)和均一成VCO2的含CO2三相包裹体(C2型)。3个成矿阶段的均一温度分别为:Ⅰ成矿阶段为290～380℃;Ⅱ成矿阶段为210～240℃;Ⅲ成矿阶段为90～190℃。成矿早阶段(Ⅰ阶段),CO2、NaCl-H2O和NaCl-H2O-CaCl2各类型均一温度相近的包裹体共生,成矿流体成分主要为CO2和NaCl-H2O,含少量H2S和CH4;成矿晚阶段(Ⅱ、Ⅲ阶段),成矿流体成分主要为NaCl-H2O。根据流体包裹体特征,结合高3He/4He比值以及在锡田花岗岩中存在大量镁铁质微粒包体,笔者认为:锡田垄上锡多金属矿床成矿物质是多来源的,成矿流体为地幔、地壳和大气水的混合产物;锡多金属来源受岩浆和围岩控制,而在成矿作用过程中尤其是成矿早阶段,地幔成矿流体可能起到了积极的甚至关键的作用。
Tin Tin Ridge on the tin polymetallic deposits in tin field Tin Tin is a large deposit. Through the petrographic and microscopic temperature analysis of the fluid inclusions of fluorite and quartz in the skarn-type and crustal alteration rock tin-polymetallic ores in Xidian, the laser Raman probe analysis of the inclusions, The results show that the tin ridges on the fluid inclusions can be divided into three types and 5 types. Category 3: Saline inclusions (type A), CO2-rich two-phase inclusions (type B) and CO2-bearing three-phase inclusions (A2 type), CO2-rich two-phase inclusions (type B), LH2O-containing CO2 three-phase inclusions (C1 type) and uniform VCO2-containing CO2 inclusions . The homogenization temperatures of the three metallogenic stages are as follows: Ⅰ the mineralization stage is 290-380 ℃; the Ⅱ mineralization stage is 210-240 ℃; and the Ⅲ metallogenic stage is 90-190 ℃. The inclusions of CO2, NaCl-H2O and NaCl-H2O-CaCl2 all have homogeneous homogenization temperature in the early stage of mineralization (Ⅰ stage), and the ore-forming fluids mainly consist of CO2 and NaCl-H2O with a small amount of H2S and CH4. Late stage (Ⅱ, Ⅲ stage), the main component of ore-forming fluid is NaCl-H2O. According to the characteristics of fluid inclusions, combined with the high 3He / 4He ratio and the presence of a large amount of mafic inclusions in the tinfield granite, the authors believe that the ore-forming materials of tin tin polymetallic deposits are multi-sourced and the ore-forming fluids are mantle , Crust and atmospheric water. The sources of tin polymetallics are controlled by magmatic and surrounding rocks. In the process of metallogenesis, especially in the early stage of metallogenesis, mantle ore-forming fluids may play a positive or even crucial role.