【作者】 吴树仁； 晏同珍； 简文星；

【Author】 Wu Shuren;Yan Tongzhen;Jian Wenxing;Institute of Geomechanics,CAGS;China University of Geoscieces;

【机构】 地质力学研究所； 中国地质大学；

【摘要】 本文利用两组大理岩岩样进行脆-韧性变形实验,一组在室温条件,围压变化范围为20—400MPa;另一组围压为50MPa,温度变化范围为15—200℃。前者发生脆-韧性转换的围压范围为50—400MPa,其中变形最敏感的围压为50—150MPa,脆-韧性转换过程表现为应变硬化作用;后者发生脆-韧性转换的温度为50—200℃,其中变形最敏感的温度为100℃左右,脆-韧性转换过程表现为应变软化作用为主。在变形(实验)岩样宏观变形行为和微观构造特征分析的基础上,讨论了岩石脆-韧性转换变形的若干标志(包括力学性质、宏观变形行为和显微构造标志等)。并阐明了大理岩脆-韧性转换变形方式是以微破裂、晶内滑移和碎裂流动作用为主。这些实验研究结果对于地壳中浅层次构造变形及表层构造软弱带成因研究具有重要意义。更多还原

【Abstract】 In this paper,two groups of marbles are used in the process of experiment on the brittle-ductile transform deformation.One is under the room temperature and the confining pressure 20-400 MPa;the other at 15- 200 C and the confining pressure 50- 150 MPa.The confining pressure of the former during which brittle-ductile transform deformation appears,is 50-400 MPa,of which the most obvious one is 50-150 MPa,and it shows strain hardening;temperature of the brittle-ductile transform of the latter is 50-200℃,of which the most obvious one is about 100℃ and it shows strain softening.On the basis of the analysis of the microscopic deformation and microscopic structures of the marbles,some marks on the brittle-ductile deformation of rocks including mechanical property,microscopic deformation and microscopic structures characteristics etc.,are discussed.Meanwhile,the important forms of the brittle-ductile transform of marbles are pointed out,that is,microcrack,intracrystalline slip and cataclastic flowage.The results of this experiment are very important to the research of the genesis of weak zone of the surface structures and the shallow structural deformation in the crust.更多还原