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加拿大地盾南部太古宙岩石构成了年代大不相同的发展历史。绿岩—花岗岩杂岩,年代是2750—2650Ma,是苏必利尔构造省大部分的典型岩石,其南部以早太古宙的混合岩化片麻岩为界,后—岩石的年代为3500Ma。花岗岩—绿岩杂岩非正式地称为绿岩层,片麻岩称为片麻岩层。以出露良好的明尼苏达州北部韦米利(Vermilion)区为例,绿岩层是由浅变质的镁铁质和长英质火山岩及碎屑岩和沉积岩构成,后者被伸长的边缘似花岗岩岩基侵入。从
Archean rocks in the southern part of the Canadian Shield constitute a very different historical development. Greenstone-granite complex, dating from 2750 to 2650 Ma, is typical of most of the Upper-Willis tectonic provinces. Its southern part is dominated by early-archean migmatitic gneiss, with a post-rock age of 3500 Ma. Granite - greenstone complex informally referred to as greenstone, gneiss is called gneiss. Taking the well-exposed Vermilion area of northern Minnesota as an example, the greenstone formation is composed of super-metamorphic mafic and feldspathic volcanics and clastic and sedimentary rocks that are elongated at the edges like granite Invaded. From