关键词: 雁列断层, 岩石大学实验, 声发射, 断层位移, 应变场

Abstract: The spatial and imporal evolution of acoustic emission, fault displacement and strain duringdeformation of compressional and extensional en-echelon faults has been studied experimentallyunder biaxial compression. The results show that two types of en-echelon faults have similar de-formation process,i.e. the deformation is predominated by fracturing and linking of jogs in thefirst stage and by sliding along faults in the second stage.However,in the compressional jog,high strain energy can be accumulated and intense release of strian and acoustic emission can beproduced,and the jog has a permanent resistance to the sliding of faults, But in the extensionaljog,rapid release of strain and strong acoustic emission event can not be produced,and the joghas almost no resistance to the sliding of faults in the second stage.The instability events causedby linkage of both jogs have obvious precursors,and the occurrence of precursors for instabilityoccured during the sliding depends on if there is strain transfer between different parts of faults.

Key words: en-echelon faults, Rock mechanical test, Acoustic emission, Fault displacement, Strain field