Temporal and spatial distribution of microfractures in granites of different structures under triaxial compression and its significance in seismology

The temporal and spatial distribution of microfracturing activity in two ki nds of granite under triaxial compression has been studied by using a new a coustic emission system. For Inada granite, there is no clear clustering of acoustic emission events in time and space, thus it is difficult to exactl y deduce the time and position of the major fracturing. While for Mayet gra nite, acoustic emission events are clustered in time and space, so the time and position of the major fracturing can be exactly predicted according to microfracturing process. Such a difference may result from the difference in deformation mode caused by different rock structures.