在片麻岩地区识别后期侵位的岩浆的流动特征,识别岩浆流动形成的岩浆岩、变质作用形成的片麻岩、韧性变形条件下形成的糜棱岩三者的差异和进行野外、室内不同环境下的判别,是现代岩石学、构造地质学需要重新审视的问题.通过对华北北缘大光顶岩体的塑性流动特征、相关的后期叠加韧性变形特征和区域变质片麻岩特征的比较,结合国内外对于岩浆塑性变形(magmatic flow)与韧性变形(solid-state flow)的比较研究,分析了在强变质岩石中如何分析和识别出岩浆的流动,这些岩浆的流动并不是区域变质作用形成的,也不是高温环境下韧性变形作用形成的,而是形成于岩浆侵位后期的冷却结晶作用.对于如何识别和分析岩浆流动提出了野外和室内的标志.%The identification of magmatic flow that intruded into the metamorphic basement and the recognition of the differences between magmatic flow and metamorphic gneiss and mylonite along the ductile shear zones constitute important problems that should be reconsidered in modem petrology and structural geology. According to a comparative study of the features of magmatic flow from Daguangding pluton on the northern margin of the North China block and the relavant superimposed ductile shear deformation and metamorphic gneiss, in combination with the investigation of magmatic flow and solid-state flow, the authors identified magmatic flow which was formed in the cooling crystallization process from the metamorphic basement during the late magmatic emplacement period. This paper provides criteria for structures and microstructures produced by magmatic flow.
展开▼
