Microstructural study of plastic flow of quartz

石英塑性流动的微观结构研究

基本信息

批准号：
62460050
负责人：
MASUDA Toshiaki
金额：
$ 5.12万
依托单位：
Shizuoka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1987
资助国家：
日本
起止时间：
1987 至 1988
项目状态：
已结题

项目摘要

(1) We collected many quartzose metamorphic rocks from the nine high P/T metamorphic belts in Japan. Their quartz microstructures are roughly classified into two groups: one is characterized by elongated grains with serrated grain boundaries which shows strong undulatory extinction; another is characterized by the equant-equigranular polygonal grains which shows no or only very slight undulatory extinction. The former will be correltated with the S-type microstructure and the latter with the P-type one of Masuda and Fujimura (1981). The former occurs in the Kamuikotan tectonic belt, Yamagami metamorphic rocks and some of the Sambagawa metamorphic belt, while the latter occurs in the Ryoke, the Yaeyama, the Nagasaki and some part of the Sambagawa metamorphic belt. According to Masuda and Fujimura (1981), the former is presumably developed at lower temperatures and faster strain rates than the latter. There are many complex microstructures which cannot be assigned to the former nor the e … More r. The classification of such microstructures is a future problem. (2) The high temperature and high pressure deformation apparatus, which was originall.y built at Nagoya University, was transported to Shizuoka University. After removing the synchronous motor-drive system and setting the computercontrolled stepping-motor system, we tried to perform a deformation experiment at temperature of 800゜C, confining pressure of 4 Kb (400 MPa) and strain rate of 10^<-6>/sec. The starting material of the experiment is the siliceous mylonite which has the foliation defined by the alternation of mica rich layers and quartz rich layers. The mylonite was uniaxially compressed parallel to the foliation, and during the experiment its layers were folded. (3) We proposed a new method that estimated relative palaeodifferential stress using microboudin structure of columnar mineral grains. This method is independent from other palaeopiezometric method such as newly recrystallized grainsize piezometer, subgrain size piezometer and dislocation density piezometer. Less

(1)我们在日本九个高P/T变质带中收集到了许多石英质变质岩，它们的石英显微结构大致分为两类：一类是细长的颗粒，晶界呈锯齿状，显示出强烈的波状消光；前者与 S 型微观结构相关，后者与 S 型微观结构相关。 Masuda和Fujimura(1981)的P型之一，前者产于Kamuikotan构造带、Yamagami变质岩和部分Sambakawa变质带，后者产于Ryoke、Yaeyama、Nagasaki和部分地区。根据Masuda和Fujimura (1981)的说法，前者是在比后者更低的温度和更快的应变速率下发育的。不能归入前者或 e 的微观结构。此类微观结构的分类是一个未来的问题 (2) 最初在名古屋大学建造的高温高压变形装置被运送到静冈大学。在去掉同步电机驱动系统并设置计算机控制步进电机系统后，我们尝试进行温度800℃、围压4Kb（400. MPa)和10^-6/秒的应变速率。实验的起始材料是硅质糜棱岩，其具有由富含云母层和富含石英层的交替所限定的叶理，糜棱岩平行于方向被单轴压缩。 (3)我们提出了一种利用柱状矿物颗粒的微布丁结构来估计相对古差异应力的新方法。其他古测压方法如新再结晶晶粒测压计、亚晶测压计和位错密度测压计较少。