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Knowledge of hidden structure defaults,stress redistribution and rock burst hazard around the longwall mining panel will allow for greater extraction efficiency with reduced safety concerns.In this paper,the stress change of the rock mass was first examined at the laboratory-scale using the ultrasonic technology.Subsequently,the active and passive seismic velocity tomograms were simultaneously applied at the field-scale with two case studies.They both demonstrate that many of the same features were evident between the active and passive tomograms.Moreover,the result that the geological discontinuity has evident linear image of the seismic tomography was indicated in the first case study.In the second case study,the results show that the seismic tomography could be used to infer stress redistribution,and determine rock burst hazard or locate the future high seismic activity zones.Ultimately,comparisons have been made between the active and passive seismic tomography,which allow us to recongnize that the active tomography is preferred to apply in the relatively accurate detection of the stress distribution and hidden structure defaults in the unmined longwall mining panel.While the passive tomography is a promising tool to continuously monitor the relatively high stress or rock burst hazard in a mine,especially in the being mined panel.This study could increase the safety and efficiency of the mining process.