Sub-microscopic Textures and Retrogressive Metamorphic Origin of Longxi Nephrite  

作　　者：王春云 张惠芬 任国浩 

机构地区：[1]Wuhan University of Technology

出　　处：《Chinese Journal Of Geochemistry》1990年第2期182-187,共6页中国地球化学学报

摘　　要：Nephrite specimens from Longxi,sichuan,prepared by ion-thinning and dispersion techniques have been studied using TEM and SAED.A series of sub-microscopic textures such as (010)multiple-chain faults and related fault terminations.(001)mechanical twinning,sub-grain boundaries or fault walls,tremolite fibrous pseudoform of talc and intergrowth of tremolite and talc with (010)as interface are revealed .By analogy of metallographic textures,characteristics and mechanisms of the process of 'deformation-recovery-recrystallization' are discussed in detail,Topotactic reaction mechanism by which tremolite retrogresses to talc was studied and a retrogressive metamorphic origin of Longxi nephrite is proposed.Nephrite specimens from Longxi,Sichuan,prepared by ion-thinning and dispersion techniques have been studied using TEM and SAED.A series of sub-microscopic textures such as (010) multi- ple-chain faults and related fault terminations,(001) mechanical twinning,sub-grain boundaries or fault walls,tremolite fibrous pseudoform of talc and intergrowth of tremolite and talc with (010) as interface are revealed.By analogy of metallographic textures,characteristics and mechanisms of the process of“deformation-recovery-recrystallization”are discussed in detail,Topotactic reaction mechanism by which tremolite retrogresses to talc was studied and a retrogressive metamorphic origin of Longxi nephrite is proposed.

关 键 词：软王 显微结构 变质作用 四川 透闪石 

分 类 号：P578.94[天文地球—矿物学]