Technology Research Of Seismic Wave Field Separation Based On SVD Method

With the precision of geological exploration be constantly improved by subgrade construction,the research and development of the comprehensive geophysical exploration technology have been promoted.The separation of seismic wave field is the first step to improve the exploration precision and realize comprehensive geophysical exploration.The existing technology of seismic wave field separation has damaged some original information or introduced other interferences in the process of data processing,and cannot completely separate multiple effective wave field components.In view of the shortcomings of the existing technology of wave field separation,a technology of seismic wave field separation based on SVD method is proposed.This method can accurately isolate the direct wave,reflected wave,refraction wave and surface wave without damaging the original information.The main work done in this thesis is as follows:(1)The propagation characteristics,time-distance curve characteristics and frequency domain characteristics of seismic wave field components are analyzed.It is determined that the seismic wave field components are more different in time domain.(2)In terms of the principle of separation of seismic waves,principle of SVD wave field separation,data linear transformation,eigenvalue of seismic wave field components,filter design and reconstruction of seismic wave field components are studied and analyzed.(3)In terms of software design,the seismic wave field separation software with the function of data import,noise reduction,interpolation,seismic wave field separation and data output is designed.The software designed using C# language based on the.NET platform.(4)In the aspect of model verification,a soft soil model is established.The software performance was verified by simulation data and data processing results.by simulation data and data processing results,and the two separation results were compared and analyzed.To sum up,this thesis studies the technology of wave field separation of shallow seismic exploration,designs and implements the software of seismic wave field separation.The software can effectively suppress the seismic wave data,interpolate the seismic waves and separate the seismic wave field components.It is convenient for the subsequent geological imaging module to further process the data and improves the accuracy of geological imaging of single seismic wave field component,greatly enhances the feasibility of comprehensive geophysical exploration.