阿尔泰伟晶岩中流体熔融包裹体成分的研究

STUDY OF COMPOSITIONS OF MELTING FLUID INCLUSIONS IN PEGMATITES, ALTAY,XINJIANG

对阿尔泰可可托海、柯鲁木特和库威伟晶岩锂辉石及绿柱石中单个流体熔融包裹体各相成分，借助激光拉曼探针进行分析，鉴定出固体相为不同硅酸盐子晶矿物，定量给出了流体相成分。根据子晶矿物和流体相成分估算了整个流体熔融包裹体的成分，并据此进一步讨论了熔体中流体的溶解度问题。流体熔融包裹体成分研究表明熔体中流体已达饱和或过饱和，流体相与熔体相发生分离，相应残余伟晶岩浆体系进入晶体＋熔体＋流体三相共存的岩浆－热液过渡阶段，从而说明阿尔泰伟晶岩成因与岩浆－热液过渡阶段有密切联系。

Laser Raman microprobe was applied to analyse the composition of different phases of individual melting fluid inclusions in spodumenes and beryls from the pegmatites of Koktokay, Kelumute and Kuwei, Altay, Xinjiang. The solid phases were identified as daughter crystal silicate minerals, and the quantitative composition of fluid phases were also obtained. The whole composition of melting fluid inclusions was estimated based on both daughter crystals and fluid phase components.The solubility of fluid in melt was also discussed. The results indicate that the fluid in melt was saturated or oversaturated, and the fluid phase fractionated from the melt phase. The corresponding residual pegmatitic magma system may have entered the magmatic-hydrothermal transitional stage in which crystal, melt and fluid phases coexist. The formation of Altay pegmatite was closely related to the magmatic-hydrothermal transitional stage.