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来自几个地盾区的证据表明,许多绿岩带是以一定的序列形式演化的:(1)浅水基底地台型沉积序列;(2)浅水平台铁镁质火山岩序列夹有硅铁建造为主的堆积物;(3)“裂谷型”火山序列(科马提岩和长英质火山岩);以及(4) 相对未变形的各种浅水盖层沉积序列。
Evidence from several shield areas shows that many greenstone belts evolve in a sequence of sequences: (1) shallow basement platform sedimentary sequences; (2) shallow-platform mafic volcanic sequences interspersed with ferrosilicon (3) “rift-type” volcanic sequences (kamamatites and marl-bearing volcanic rocks); and (4) sedimentary sequences of relatively undeformed various shallow-water caprocks.