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本文对山西五台山地区与超镁铁质岩密切共生的含蓝晶石的各类片岩进行了研究。研究发现,在蓝晶石铝直闪石片岩中存在一种特殊的冠状体结构,即蓝晶石和铝直闪石被它们之间内圈的十字石十刚玉十绿泥石和外圈的堇青石所包绕。这种特殊的反应边结构,说明岩石曾处于较高的压力条件下(0.9~1.4GPa),然后经历了明显的近等温的减压过程。其它类型的含蓝晶石片岩,也包含了高压变质矿物组合,并经历了同样的变质演化过程。这种演化历史与该区经历了古洋壳俯冲,消减,弧陆碰撞和伴随的迅速折返和抬升是密切有关的。
In this paper, the kyanite-bearing schist that is closely intergrowth with ultramafic rocks in Wutai Mountain, Shanxi Province are studied. It is found that there is a special coronal structure in the kyanite Al-chalchite schist, namely, the kyanite and Al-feldspar are intercalated with the corundum and the outer cordierite Surrounded. This special reaction edge structure indicates that the rock was under high pressure (0.9 ~ 1.4GPa) and then experienced a significant near-isothermal decompression process. Other types of kyanite-bearing schist include high-pressure metamorphic mineral assemblages that have undergone the same metamorphic evolution. This evolutionary history is closely related to the exhumation and subduction of the ancient oceanic crust, the collision with the arc and the accompanying rapid reentry and uplift.