Dependence of the AE maximum burst amplitude on the deformation mechanism in some rocks

Maximum amplitude of acoustic emission events in 10 second intervals were measured in the samrles of dolomite and sandstonc under uniaxiall comrressive load.
The observed sudden increase of the maximum amplitude, in a function of load, indicates the beginning of the unstable propagation of microfractures, leading to uncontrol¬led failure of a sample. The maximum amplitude dependence on load, as directly related to the AE source mechanism, can be used in prediction of the rock damage in situ.