Abstract:Through analyzing field test data,the paper studied spreading character of seismic wave in a condition of delayed blast.Adopting forward modeling and other mathematical tools,the changing rule of dominant frequency,band width and energy of seismic wave was discussed and the influence of incident angle on above-mentioned factors was analyzed in a condition of delayed blast.The research results showed that in a condition of same charge size,using explosive mode of delayed blast can enlarge dominant frequency of seismic wave,widen its band and strengthen energy of down-going seismic wave;the distortion of seismic waveform and its spectrum caused by different incident angle is very small when delayed blast is carried out within an incident scope of conventional seismic exploration.The field stack sections show that the method can improve exploration resolution in some degree.