中文摘要:本文通过对伟晶岩矿物包裹体的研究，发现伟晶岩和似伟晶岩的矿物包裹体均以气液包裹体为主，不同矿化伟晶岩的包裹体不相同。包裹体的气体成分以水蒸气为主，有一定量的CH4、N2、O2及CO。成矿伟晶岩包裹体的电导率较高，富Na+、K+而贫Ca2+和Mg2+，阴离子成分有较大差异，这与矿化元素在成矿溶液中的不同迁移形式有关。作者还测定了包裹体溶液中成矿金属元素和稀土元素的含量，这对于探讨成矿物质来源和地化找矿标志均有一定意义。
Abstract:Genetic types of mineral inclusions, homogenization temperatures, composition of cations and anions, contents of metallogenic elements and REE distribution patterns of different mineralized pegmatites (containing REE, Nb, Be, and Au respectively) and some pegmatoids have been studied m this paper. On such a basis, the authors further discuss the formation conditions of pegmatites, the difference iii formation conditions between pegmatites and pegmatoids, the characteristics of ore-forming solutions for mineralized pegmzttites, the distinction in ore-forming solutions between different mineralized pegmatites and the possibility of using REE distribution patterns of liquid inclusions to investigate the ore-forming material sources of pegmatites. Although the inclusions in minerals from pegmatites and pegmatoids are mainly gaseous-liquid ones, they show different characteristics in different mineralized pegmatitis. Gaseous and liquid CO2-containing triphase inclusions are mainly contained in REE pegmatite, while triphase inclusions with NaCl daughter crystal occur in the Nb pegmatite, which is somewhat similar to things with the corresponding mineralized granites. The homogenization temperature of the pegmatites ranges between 140℃ and 270℃, lower than the formation temperature of granites. This suggests that the mineralized pegmatites and pegmatoids must have resulted from the residual magmatic fluids differentiated from mineralized granites under a more closed condition. The gas components of inclusion are mainly water vapors, with some CO2 and small amounts of CH4, N2, O2 and CO. The inclusions in the REE pegmatite are enriched in CO2. Compared with pegmatite, pegmatoid contains more gases, especially CH4 gas, caused probably by the factor that pegmatoid usually occurs at the top of a rock body under more closed condition and without any migration. The oxygen fugacity under which each pegmatite was formed varies in the range of lgfO2 = -36.2-49.8. REE pegmatite was formed under relatively oxidizing condition, while the gold-bearing pegmatite occurred under relatively reductive condition. As for the liquid phase components the inclusion solutions of mineralized pegmatite with comparatively high electroconductivity have relatively high ion contents. They are also enriched in Na+ and K+ but depleted in Ca2+ and Mg2+. Different sorts of pegmatites are noted for diverse anion components: REE pegmatite is enriched in HCO3-; Nb pegmatite is abundant in F-; gold-bearing pegmatite is rich in Cl-; and Be pegmatite contains certain amounts of both F- and Cl-. These differences must have had something to do with the migration forms of these mineralizing elements in the ore-forming fluids. In this study, the authors have also determined the contents of metallogenic elements in the inclusions. Each sort of mineralized pegmatite is characterized by high content of the corresponding metallogenic element, and this serves as a good indicator in geochemical are prospecting. In REE distribution, the inclusion solution is similar to the bulk rock and every mineralized pegmatite is similar to corresponding mineralized granite. This suggests that REE distribution of the inclusion solution might be used to investigate the sources of ore-forming materials.
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储同庆，王鹤年.1987.不同矿化伟晶岩矿物包裹体的研究[J].矿床地质,6(3):77~84.1987.A Study Of Inclusions In Mnierals From Different Mineralized Pegmatites[J].Mineral Deposits6(3):77~84
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