Temporal and spatial evolution law of characteristic parameters for coal rock fracture induced seismic wave

Quantitative study of the temporal and spatial evolution of seismic wave characteristic parameters is of great significance for accurately identifying the P-wave and S-wave in seismic waves and improving the accuracy in localizing microseismic events. Based on the field-measured seismic wave data of the Wudong coal mine, this paper studies the temporal and spatial evolution law of seismic wave amplitude and frequency. The time-window sliding algorithm is proposed to process the amplitude and frequency content of the seismic wave. The obtained instantaneous change rates of amplitude and frequency can accurately characterize the arrival times of P-wave and S-wave, and assist in automatically pinpointing the corresponding seismic waves. The amplitude of the seismic wave recorded by seismic sensors located at different spatial locations from the source reveals that the attenuation decreases gradually with the increase of the propagation distance and that the attenuation rate gradually slows down. It is noted that there are some discrepancies in the amplitude and frequency of the seismic waves recorded by different seismic sensors yet with the same distance from the source. Based on the P-wave and S-wave component diagrams of the seismic displacement field of coal and rock rupture, combined with the laws and differences of the amplitude and frequency of the seismic wave signals at different spatial locations, a new method is proposed to roughly determine the rupture source direction. This study provides a new perspective that can be instrumental for a more comprehensive study of the rupture source direction generated by on-site microseismic events.