Characteristics and Geological Meaning of Metamorphic Zonation of Top Laguigangri Metamorphic Core Complex, Tibet
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摘要: 藏南拉轨岗日由一系列链状的热穹隆构成, 总体呈东西向延伸, 每一个热穹隆是一个变质核杂岩, 核部发育大量变质岩, 基底与盖层之间发育拆离断层.通过对拉轨岗日变质带及其特征变质矿物进行化学成分分析和温度压力估算, 得出拉轨岗日变质带的分带规律及矿物成分、变质温度、压力、深度的变化规律, 为拉轨岗日变质核杂岩的热活动提供了佐证.Abstract: Laguigangri Mountains are composed of a series of chain-like swellings trending west and east. They all are vaults where there are a lot of metamorphic rocks and detachment faults, and so they are naturally related to each other. The research of chemical composition and metamorphic zonation and estimation of p-T of characteristic metamorphic minerals from metamorphic zone in Laguigangri has revealed the regularity of composition, temperature and pressure and metamorphic depth. This will evidence the activities of the metamorphic core and the detachment fault.
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Key words:
- metamorphic zonation /
- chemical composition /
- metamorphic core complex /
- Laguigangri /
- Tibet
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表 1 石榴子石化学组成
Table 1. Chemical compositions of garnets
表 2 白云母化学组成(原子系数)
Table 2. Chemical compositions of muscovite
表 3 绿泥石化学成分(原子系数)
Table 3. Chemical compositions of Chl
表 4 黑云母化学组成(原子系数)
Table 4. Chemical compositions of biotite
表 5 由石榴子石-黑云母、白云母计算的p、T、D、FMG
Table 5. p, T, D, FMG value
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