Analysis of frequency characteristics of microseismic signals induced by hard rock mining.

To study the frequency characteristics of mining-induced microseismic signals in hard rock mines, spectrum analysis combined with energy spectral density method was used to analyze the vibration signals generated by microseismic activities during mining, and the energy distribution of microseismic signals induced by hard rock bodies was obtained. The results showed that the attenuation of the microseismic wave propagation affected the change of the energy proportion in each frequency interval. As the propagation distance increased, the energy proportion in the low frequency region increased and the energy proportion in the middle and high frequency regions decreased. As the wave propagated to about 200 m. the frequency interval with higher energy proportions changed significantly. In the wave propagation range of 200 to 500 m. the frequency range with high energy proportion was mainly in the range of 20 -- 40 Hz,and the interval did not change much and was relatively stable. Using the frequency characteristics of the microseismic wave propagation process induced by the hard rock mining mentioned above has certain reference value for improving the identification of microseismic events induced by the hard rock body and the filtering of the focal mechanism calculation. [ABSTRACT FROM AUTHOR]