轴向分布式药包激发地震波场模型

The amplitude-frequency characters of the seismic wave excited by the explosive source directly affect the seismic exploration accuracy. In order to reveal the characteristic law of the amplitude and frequency of the seismic wave field excited by an axially distributed explosive, the study on the calculation method of the seismic wave field of the axially distributed explosive was proposed. Based on the spherical cavity source model, the calculation method of the seismic wave field excited by the axially distributed explosive source was obtained by using the superposition method, and the seismic wave field model excited by the axially distributed charge was established. This model can describe the characteristics of the seismic wave field of distributed explosive sources in seismic exploration. Comparison with numerical simulation shows that the error between the theoretical model and the numerical model is within 5% in the radial direction, and the error between the theoretical model and the numerical model is within 3.4% in the axial direction. Compared with the field experiment results, the theoretical model seismic wave vibration velocity error is within 10% when the blast center distance is greater than 14 m. The calculation accuracy increases with the increase of the distance, and the error is less than 6% when the distance is greater than 24 m. When the blast center distance is the same, the vibration speed in the axial direction is greater than the vibration speed in the radial direction. The difference between the two decreases with the increase of the blast center distance. When the blast center distance is 9.8 times the total length of the charge, the axial direction is the vibration speed difference in the radial direction is within 5%, and the frequency of the seismic wave is higher. The research shows that the model can accurately describe the amplitude-frequency character of the seismic wave excited by the axially-distributed explosive.