Forward Modeling Simulation Of Seismic Wave Advance Exploration In Mine Roadway

In the process of tunneling and coal mining, there are often geological abnormalities such as faults, which are geological factors that induce the occurrence of coal and gas outburst, mine water inrush and so on, which not only affect the progress of tunneling. It will cause casualties and other accidents, so it is necessary to carry out the study of the occurrence state of the fault in front of the fault.In this paper, the wave equation of isotropic medium is introduced by the three basic equations of elastic theory. And the first-order velocity stress wave equation is further deduced. According to the finite difference principle of the staggered grid, we derive the finite difference form of the first order velocity stress equation, and give the initial conditions, the stability condition and the specific form of the focal function. The flux correction transmission combined with the improved differential accuracy eliminates numerical dispersion and results in a clear wavefront snapshot. The boundary wave is treated by the perfect matching layer, which absorbs the boundary reflection well, and simulates the elastic wave propagation law which is close to the actual space condition.Based on the theory of elastic wave, the finite difference elastic wave field numerical simulation technique is used to simulate the faults with different inclination angles in front of the face. The seismic forward modeling of the three - layer media is simulated,And the different wave field response characteristics of different thickness faults are obtained,As the distance between the geological interface and the receiving arrangement increases, the reflected S wave energy decays significantly,and the reflected P wave is very clear and the energy is strong.In this paper, the geological prospecting of the 1302 working face of a co al mine is obtained by using the mine prospecting instrument, and the dis tance between the fault and the detection point is obtained.The seismic re cords obtained by the mine prospecting apparatus are compared with the seismic records simulated by the forward modeling of the fault angle of 60°. It can be concluded that the inclination angle of the fault in front of the 1302 working face is 60 degrees, so the forward modeling of the seis mic exploration of the mine roadway Coal mining has a certain guiding s ignificance.It is helpful to find out the occurrence of the front fault in the front of the face by combining the forward modeling simulation of the elastic wave field propagation characteristics of the faults with different inclination angles in front of the face. It is of great significance to reduce the influence of fault on roadway excavation and realize the safe and efficient production of coal mine.