辉石13.5多形体的高分辨电镜研究  

A Study of 13.5 Blocks in Pyroxenes under High Resolution Transmission Electron Microscope

作　　者：王岩国[1] 黄婉康 

机构地区：[1]中国科学院金属研究所,沈阳110015 [2]中国科学院地球化学研究所广州分部,广州510640

出　　处：《岩石矿物学杂志》1992年第3期239-242,T001,共5页Acta Petrologica et Mineralogica

基　　金：国家自然科学基金

摘　　要：利用高分辨电子显微术观察了球粒陨石中的顽火辉石和斜长岩中的紫苏辉石,发现沿a轴方向有周期为13.5?和22.5?两种多形体与单斜辉石及斜方辉石紧密连生。这些新多形体的产生与高温相向低温相转变过程中Si—O链的错排有关。利用高分辨像推测了Si—O链在两种多形体中的排列方式。同时,还观察和讨论了新多形结构向单斜和斜方辉石的转变。The 13.5A and 22.5A blocks along a-axis of pyroxenes from QingZhenchondrite and anorthosite were observed under HRTEM. This kind of odd-layered stacking sequence arises from the stacking faults of Si-O chains inpyroxenes in the process of Phase transformation. According to differentstacking faults of Si-O chains, the 13.5A blocks could be arranged as Si(A)Si(B)Si(B′)Si(A) and Si(B) Si(A) Si(A) Si(B), with the former belonging to theorthorhombic system while the latter. to the monoclinic system. In orthopy-roxene from anorthosite, the 13.5A+22.5A blocks were transformed toorthopyroxene+clinopyroxene, which is considered to have resulted from thechange of Si(A)?Si (B′).

关 键 词：辉石 多形 电子显微术 电镜 

分 类 号：P578.954[天文地球—矿物学]