浙江陈蔡群孔兹岩系的变质地质学研究

Metamorphic Geology of khondalite series from Chencai Group in Zhejiang province

本文对浙江陈蔡群孔兹岩系的变质岩石组合、原岩建造、变质作用、成矿作用以及地壳早期历史的演化进行了研究．浙江陈察群孔兹岩系经受了多期变质变形、其主变质期发生于加里东早期，包括从低角门岩相到高角门岩相两阶段变质．中元古开始的扩张裂陷作用、使浙闽地块逐渐脱离江南古陆形成古岛弧，遂有陈蔡群孔兹岩系的原岩沉积、原岩建造包含了两个大的火山—沉积旋回．加里东运动使古岛弧、弧后盆地和江南古陆联为一体，形成统一的稳定陆块．

his paper will discuss on rock assemblages mineral association、protollths formation、depositional environment、metamorphism、mineral resources and its crust evolution of the Chencai khondalite series in Zhejiang Province.The metamorphic formation of Chencai Khondalite series is predominant of gneisses、with some amphibolites、leplites、quartz schists and marbles.The Khondalite series of Chencai Group was regionally metamorphosed during the late Proterozoic to early Palaeozoic.The metamorphic rocks have undergone two episdes of metamorphism from low amphibolite facies to high amphibolite factes.At the stage of low amphibolite facies,in high-aluminium politic rocks has garnet、Kyanite and staurolite formed by metamorphism.The P-T conditions of the stage are inferred to be 530～ 580℃、0.4～ 0 5GPa.At the stage of high amphibolite facies that muscovite in metapelites was converted into sillimanite and potash-feldspar in the presence of quartz.The P-T conditions of this stage are 600～700℃、0.6～0.8GPa.The protoliths formation of Chencai Khondalite series was formed in ocean arc islan.As a result of rifting started in middle Proterozoic,Zhejiang-Fujian block gradually departed from Jiannan old land,and Zhejiang-Fujian arc land was formed.The protoliths formation of Chencai Khondalite series was deposited.it consists of two large volcanic-sedimentary cycles,The Caledonian event makes the old-arc land and back-arc basin linked with Jiannan old land,and the united stable continental block has been formed.