Abstract：In order to study the mechanism and predict the occurrence range of dynamic risk caused by underground mining，the dynamic events in a practical exploitation approaching to faults are investigated by using numerical method following the actual mining sequence on a typical cross-section E5200 in Laohutai colliery，Fushun. The dynamic risk area regionalization is specifically investigated，in which the criterion in terms of 3 g occurrence is proposed to diagnose the rockburst in responding positions. Based on the concept of 3 g envelope，the potential domain with dynamic risk is primarily identified. The effect of the faults is clarified when dynamic regionalization is carried out. The mining depth and the existence of faults are the main controlling factors of dynamic tremors under the complicated field situations. The presented work shows that there are directly proportional relationship between the radii of 3 g envelope and the mining induced tremor depth，and the deeper the mining is，the larger the radii of 3 g envelope will be. With regard to this discovery，the radii of the 3 g envelope are determined when sequential convergence methodology is employed.
