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古老变质岩系主要由前人称为“片麻岩系”和“结晶片岩系”两大套岩系组成。当地球成球之后,表面首先形成一层“基性焦壳”,在热封闭条件下,壳内产生花岗岩岩浆源,注入此原始地壳,并引起变质作用,形成基性正片麻岩地壳——第一层结晶地壳。然后,固体地壳发生形变和破裂,产生侵蚀、沉积,并伴随着岩浆活动、变质作用形成副片麻岩类——第二层结晶地壳。由此,本文以北京及其外围地区的古老变质岩系为依据,阐述了地球的形成和演化规律。
The ancient metamorphic rocks are mainly composed of two major rock series called “gneiss series” and “crystalline schist series”. When the Earth becomes a ball, the surface first forms a layer of “basic coke shell”. Under the heat-sealed condition, the granite magma source is generated in the shell and injected into the original crust, causing metamorphism and forming the basement gneiss crust- The first layer of crystalline crust. The solid crust then deforms and ruptures, creating erosion and sedimentation with magmatic activity that forms the paragneiss - the second crystalline crust. Therefore, based on the ancient metamorphic rocks in Beijing and its peripheral areas, this paper expounds the formation and evolution of the earth.