摘要
借助新型声发射观测系统,对两种构造活动模式转变对b值的影响进行了初步实验研究.第一个实验通过改变加载方向使构造活动模式从挤压型雁列变为拉张型雁列,得出前一阶段b值比后一阶段要高;第二个实验通过持续加载使拉张型雁列变为拐折断层,与第一个实验类似,前一阶段b值比后一阶段要高.说明b值可能蕴含有构造活动模式的某些特征,有可能成为分析区域构造活动模式的一种新手段.
A preliminary study of b value of rocks with two kinds of structural models has been made on the base of a new acoustic emission recording system. It shows that b value of the sample decreases obviously when the sample with compressive en echelon faults changes into a tensile one after interchange occurs between stress axis σ_1 and σ_2. A similar example is observed when the sample with tensile en echelon faults changes into that with a bend fault after two segments of the en echelon fault linking up. These facts indicate that the variation of b value may contain the information of the regional dominant structural model. Therefore, b-value analyses could be a new method for studying regional dominant structural models.
出处
《地震学报》
CSCD
北大核心
2005年第3期317-323,共7页
Acta Seismologica Sinica
基金
国家自然科学基金项目(40072067)
国家"十五"科技攻关项目(2004BA601B01)资助.
关键词
声发射b值
构造活动模式
雁列断层
拐折断层
b value of acoustic emission
structural model
en echelon fault
bend fault
