The Analysis Of Near Surface Structural Change On Static Correction

Ideally, seismic data acquisition should take on a horzontal plane,and the thickness,velocity in space don't change.In other words,the time delay caused in near surface by shotpoints and detection point should be the same. The seismic wave did not being affected generally in easy near surface or plains region.In fact,this kind of near surface is fewer.So the problem of static correction is one of the keys of the seismic exploration. Near surface structural change is close related to the effect of static correction.The study of near surface structural change on static correction can give us perceptual cognition to static correction.Each process should take great effort to improve the effect of static correction.First,this thesis elaborates the method of static correction going,then review developing process and research situation of ray tracing and tomography. Second,the dissemination rule and time-distance curve equation of seismic wave is analysised,following that, the basic principle and step of tomography is introduced.Finally,different near surface models are established to correct by tomography.we can observe the effect in topography changes,thickness and velocity variation of low-velocity-layer,velocity variation of high-velocity-layer and the change of datum plane. Draw a conclusion by contrast and analy the static according to the velocity model which get from our method. Give suggestion of future work in accordance with the conclusion,which had laid a good foundation for solving the static correction issue of the different areas.