Ray Tracing Of Multi-component Seismic Waves In VTI Media And Analysis On Anisotropic Parameters

Forward of seismic data and analysis on parameter play an important role in seismic exploration. Usually, we assume all the media on earth is isotropic, but it is actually anisotropic. Propagation of seismic wave in anisotropic media is more complex than that in isotropic media, so it is important that how to simulate the propagation of seismic wave in anisotropic media and do analysis on anisotropic parameters. Velocity analysis is a key problem in seismic data processing. To realize high-accuracy velocity analysis, we must take anisotropic parameters into account.Based on anisotropic theory, this paper analyzes the rule of phase velocity and group velocity in transverse isotropic media, discusses the characteristic of ray in anisotropic media. It does ray tracing of PP wave and PSV wave in VTI media. Except for the travel time is calculated, the approximate root of reflection and transmission coefficients is also calculated. And by calculating the coefficients, energy is distributed in the process of seismic wave propagation, which simulates more perfectly the propagation of seismic wave in anisotropic media.Anisotropic parameters have an effect on P-wave data, but it is not presented evidently on seismic record. And S-wave data is sensitive to anisotropic parameters. So, when doing parameter analysis on anisotropic media, it is necessary to do multicomponent exploration. The study of anisotropic parameters is now a hot research subject, but the technique of parameter analysis and the accuracy of spectrum of anisotropic parameters need further improvement. This paper still adopts the measurements of single scan on PP wave data, and improves the method of PSV wave data by using efficiently the multi-component, which tries to get rid of our blindness of setting the initial parameters. Selective-correlation method by Ceils in2002in velocity analysis is used in anisotropic parameter analysis in this paper, which improves the accuracy of parameter spectrum.Fortran is a kind of numerical computation language with a high calculating speed and VC++is a kind of language providing a strong function of developing a mutual interface. By mix-programming of Fortran and VC++, this paper develops a set of software with the modules of seismic wave simulation, velocity analysis, parameter analysis on isotropic and anisotropic media.The innovative achievements in this paper are as follows:(1) Energy of seismic wave is distributed by calculating the approximate root of reflection and transmission coefficients in ray tracing of PP wave and PSV wave in VTI media, which makes seismic record to be simulated more reasonable.(2) Selective-correlation method in velocity analysis is used in anisotropic parameter analysis to calculate parameter spectrum, which improves the accuracy of parameter spectrum.(3) The improved method of PSV wave data are put forward, which uses fully the information of velocity and parameter analysis on PP wave data to estimate the parameter of PSV wave at first, and then calculate parameter spectrum. It increases speed and omits the need for excessive affixture calculation to improve efficiency of anisotropic parameter analysis on PSV wave data.