苏北元古界海州群变质作用

The Metamorphism of Proterozoic Haizhou Group, Northern Jiangsu

苏北东海—连云港一带的前震旦变质地层,据近年来的研究重新定为上太古界东海群和元古界海州群。本文主要是对海州群的变质作用进行讨论。

The Proterozoic Haizhou group can be divided into low Proterozoic Jinpingand middle-upper Proterozoic Yuntai subgroups. The Jinping subgroup belongs to the metamorphic apatitolite-schist formation and the non—metamorphic apatire—bearing dolomitic carbonate—argiUo—arenaceous sedimentary and the Yuntai subgroup—metamorphic leptynite formation and nonmetamorphic intermediate acidic volcanic—clastic formation. The metamorphic formations can be divided into high greenschist facies consiting of albite—amphibole zone and low greenschist facies including the albite—actinolite zone. Having study of the metamorphic minerals and their deformations the authors suggest that the Haizhou group belongs to the high-pressure metamorphic series of regional dynamometamorphism.