Research Advances of Melt Inclusions in High-Grade Metamorphic Rocks
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摘要: 高级变质岩中的熔体包裹体为包裹于寄主矿物(石榴子石、锆石等)中的熔体滴,主要由子晶矿物、玻璃和一些偶然捕获的固相矿物组成.最近10年来,熔体包裹体已经成为研究区域变质岩部分熔融作用的新手段和新途径.熔体包裹体粒径通常 < 20 μm,微小的尺度对熔体包裹体识别与分析提出巨大挑战.为此系统总结了熔体包裹体的识别方法、结构特征、化学成分分析方法,并指出熔体包裹体研究对于部分熔融的识别、部分熔融发生的温压条件、机制和流体状态的限定等具有重要的意义.Abstract: Melt inclusions in high-grade metamorphic rocks are melt drops enclosed in host minerals such as garnet and zircon, which are composed of daughter minerals, glass and other accidently trapped solid minerals. In the last decade, melt inclusions have become a new approach to the study of partial melting process in high-grade metamorphic rocks. It is generally difficult to identify and analyze melt inclusions since they are mostly less than 20 μm in diameter. This paper systematically summarizes the identification methods, microstructural features, and chemical investigation methods. The significance of melt inclusions on the identification of partial melting and constraints of the P-T condition, mechanism and fluid regime of partial melting are also discussed.
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Key words:
- melt inclusion /
- host mineral /
- partial melting /
- migmatite /
- petrology
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图 1 透射光显微镜下石榴子石(a)和锆石(b)中的熔体包裹体
图a修改自Bartoli et al.(2013b);图b来自威海地区混合岩样品
Fig. 1. Plane-polarized light photomicrographs showing garnet (a) and zircon (b) contain abundant melt inclusions
图 2 花岗质玻璃标样的拉曼谱图
修改自Ferrero et al.(2016a);玻璃标样来自Morgan and London(2005)
Fig. 2. The Raman spectrum of standard granitic glass
图 3 典型熔体包裹体的BSE图像
其中图a、图b来自威海混合岩样品;图c、图e修改自Ferrero et al.(2012);图f修改自Ferrero et al.(2016b).蓝色箭头代表熔体包裹体爆裂形成的爆裂纹;红色箭头为分布于熔体包裹体中的孔隙
Fig. 3. BSE images of typical melt inclusions
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