地壳演化过程中铬铝云母标型性探讨

对于早期地壳性质及晚期地壳演化的研究一直是地质学界关注的课题,本文将以矿物系统发生史研究为指导,通过详细研究全球范围内103个(包括笔者完成的42个样品)铬铝云母样品在地壳中的分布规律及其化学成分和矿物种标型特征时空演化规律,认为早期地壳中幔源物质铬与壳源物质铝交互作用导致铬铝云母的形成,从而为认识早期地壳具有硅铝质组成提供了佐证。在晚期地壳演化尤其是成矿作用方面,提出了铬铝云母标型性特征,确立了铬铝云母在自然历史中固有的位置和作用。

TYPOMORPHISM OF ALUMINO-CHROMIAN MICA IN CRUSTAL EVOLUTION

This paper deals with the typomorphism of alumino-chromian micas from the view-point of mineralogical phylogeny. The authors have investigated the early origin and late evolution of the crust based on 103 samples from different part of the world including 42 Chinese samples analyzed by the authors. The features point to the conclusion that the elements Cr and Al are rich in mantle-derived rocks and crust-derived rocks respectively. Alumino-chromian micas are mainly generated by the crust-mantle interaction in the earlier geological times or related to remobiliza-tion in crystalline basement in the later geological time and sometimes occur in altered ultrabasic rocks in ophiolites. The characteristics of evolution of alumino-chromian micas will be helpful to recognize the geological history from early origin to late evolution of the crust, especially the ore formation. The position of alumino-chromian micas in geological history is also affirmed.