摘要
在温度为８００～９００℃，围压为１ＧＰａ的条件下对基性麻粒岩进行了压缩变形实验。样品变形处于半脆性域，以出现非破裂的准韧性剪切带为特征。提出了剪切带是由样品的原始缺陷向外稳态扩展而形成的机制，可用稍加改变的流变介质断裂力学原理对这种扩展过程进行说明；并将此机制推广到剪切带的形成中。
A mafic granulite from Shanxi Province, North China has been deformed at a confining pressure of 1 GPa and temperatures of 800￣900℃. Optical micrographs of deformed samples show that different scales of semi brittle ductile shear zones (SBDSZ) occur with different strains. A mechanism for the forming of SBDSZ, briefly to say, is to nucleate at pre existing weakness first and then to develop from this weakness steadily, which can be expressed by slightly revised theory of fracture mechanics of rheological materials. The experimental result is of significance in discussing the formation of ductile shear zones in the continental lower crust.
出处
《成都理工学院学报》
CSCD
1997年第3期36-41,共6页
Journal of Chengdu University of Technology
基金
中国科学院地球动力学高温高压开放实验室资助
国家自然科学基金
关键词
麻粒岩
剪切带
形成机制
实验研究
基性麻粒岩
mafic granulite
deformation experiment
mechanism for shear zone
continental lower crust
