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引言太古代地壳一般由下列几个单元或其中之一所组成:a)大面积的花岗岩一片麻岩区,b)绿岩带及与其伴生的花岗质深成岩,c)麻粒岩带。这几个单元各自的地质动力学含义及其相互间的关系,至今仍然是个争论不休的问题,而且对太古代地壳演化的成因模式也没有一致意见(Windley,1977)。本文论述芬兰拉普兰太古界中有三个基本组成单元产出的一个较小也区(约55000平方公里)。目的是概述这些岩石类型的分布,讨论它们的变质和构造演化,进而提出一
Introduction Archean crusts are generally composed of, or consist of, one or more of the following units: a) a large area of granitic gneiss, b) a greenstone belt and associated granitic plutons, c) granulite zones. The geodynamic dynamics of each of these units and their relationship to each other are still debated so far, and there is no consensus on the generative pattern of the Archean crustal evolution (Windley, 1977). This article discusses a smaller section (about 55,000 km2) of the three basic units produced in the Archean Laplace of Finland. The purpose is to outline the distribution of these rock types, discuss their metamorphism and tectonic evolution, and then propose a