Mechanism of microseism-inducdrock burst revealed by microseismic monitoring

In the sublevel caving longwall face #3201 of Chaoyang Coal Mine,an abnormal phenomenon is detected that the amplitude of detector receiving microseismic wave earlier is bigger than the one receiving microseismic wave later by using high-precision microseismic monitoring system and then a strong underground vibration is felt.In response to this anomaly,the layout of high-precision microseismic monitoring system and system calibration is introduced.Through the abnormal waveform data analysis and preliminary positioning,that the results of microseismic positioning do not meet the requirements of positioning accuracy is discovered,thus negating the basic assumptions of considering the record of the microseismic data as one source to locate.On this basis,a hypothesis is put forward,that is,the mechanism of microseim-induced rock burst is the pattern of the vibration wave of the inital microseismic source inducing another microseismic source by the vibrational failure of s-wave,and the hypothesis is proved strictly.Considering of underground pressure and stratum control and the results of long-term microseismic monitoring,the location of the induced microseismic source is found exactly under the high-stress area of mining-induced stress field and tectonic stress field,which is further proof of the above hypothesis and makes it clear that the induced microseismic source is located in the high-stress areas under the influence of coupling factors.