摘要
研究了大别山区剪切构造带内榴辉岩在退变质阶段塑性变形过程中的成分变异、体积变化和流体流动特征,得到:(1)随着变形程度的增强,榴辉岩中除Al2O3,P2O5和Th的含量基本保持不变外,其他组分或元素都发生了明显的变异;(2)SiO2在超高压榴辉岩带中表现为明显的流失,而在高压中温榴辉岩带内表现为明显的获得;(3)从榴辉岩到榴闪岩再到榴云角闪片岩的退变质阶段变形过程中,岩石体积发生了明显扩容,其体积变化率为-3.5%~-28%;(4)流体/岩石比值约为1~50.1。
Based on the study of the composition variation,volume change and fluid flow of the eclogites in the shear zones in Dabie mountains,the conclusions are summarizedas:(1)almost all of elements,except for A1,P and Th in the eclogites,had been varied in the shear zones during retrograde metamorphism processes;(2)Si was gained in the high-pressure and middle temperature eclogite zone,but lost in the ultra-high pressure eclogite zone;(3)the dilation,with the rate varying from 3.5% to 28% in volume,occurred from eclogites to amphibole schists in the shear zones during retrograde metamorphism processes and (4) the fluid flow and volume change are two key factors for the composition variation of the eclogites in the shear zones in Dabie Mountains.
出处
《地球科学(中国地质大学学报)》
CSCD
北大核心
1996年第5期508-512,共5页
Earth Science-Journal of China University of Geosciences
基金
国家计委国土司专项基金
地质矿产部壳幔体系组成
物质交换及动力学开放研究实验室基金
关键词
成分变异
体积变化
榴辉岩
大别山
剪切构造带
composition variation
volume change
fluid flow
eclogite
Dabie Mountains.