摘要
江山—绍兴断裂带代表了会稽元古代地体和陈蔡元古代地体的碰撞拼贴带。双溪坞群和陈蔡群在岩石组合和地质地球化学方面存在着很大的差异,分属于会稽地体和陈蔡地体的物质组成。地体碰撞始于距今10 Ga年前,结束于900～850Ma年前。拼贴带内存在着由双溪坞群、陈蔡群、超镁铁质和镁铁质岩块及洋壳碎片组成的构造混杂体。本文还用地体碰撞拼贴的观点解释了两地体的变质变形差异及西裘和璜山石英闪长岩体的成因。
Jiangshan-Shaoxing fault zone represents the collision-collage zonebetween Kuaiji Proterozoic terrane and Chencai Proterozoic terrane.Shuangxiwu Group and Chencai Group have a great difference betweenrock associations and geochemistry and belong to Kuaiji terrane andChencai terrane, respectively. The terrane collision-collage began 1000 Mato the present and ended 850～900 Ma to the present, formed tectonicmelange consisting of Shuangxiwu Group, Chencai Group and ultramafic,mafic as well as oceanic crust fragments. The paper well explains themetamorphism and deformation difference between two terranes and theorigin of quartz diorite bodies such as Xiqiu and Huangshan from thepoint of view of analysis of terrane collision-collage.
关键词
元古代
断裂带
俯冲带
混杂岩
浙江/地体
碰撞拼贴带
Proterozoic era
fault zone
subducted zone
melange
Zhejiang/terrane
collision-collage zone
