Phase Correlation Velocity Analysis And Application Of Anisotropic Media

The velocity analysis plays a very important role in seismic survey data processing.With the deepening of the depth of seismic exploration,the accuracy of seismic exploration is getting higher and higher.However,due to the fact that the underground media often behaves as anisotropy,the approximate velocity analysis based on isotropic media has been unable to meet the requirements of high precision seismic exploration.In-depth study of anisotropy is very helpful in solving the problem of long-range alignment correction.It is equally important for the exploration of deep-level target layers in oil and gas exploration and development,as well as improving the accuracy of velocity analysis and improving the accuracy of time-depth conversion problems.So when we are carrying out multi-wave seismic exploration,we need to obtain the anisotropic medium time-distance curve fitting formula,but also to analyze the relationship between formation parameters and speed,make full use of a variety of information for processing.After studying and understanding the theory of anisotropy and the analysis of anisotropic velocity analysis,this paper summarizes the previous research results and briefly describes the theory of anisotropy.At the same time,it introduces the normal time difference calculation of seismic wave in anisotropic media The derivation of the formula.In addition,on the basis of studying the relevant literature of scholars before,we draw the formula of longitudinal wave and converted wave time-delay curve in VTI medium,and analyze the relationship between anisotropy parameter and velocity and time-distance curve.In addition,we compare the time-distance curve and velocity spectrum in isotropic cases.In addition,based on the research progress of speed analysis at home and abroad,this paper proposes an improved phase correlation velocity analysis method for the existing problems of the predecessors' methods,and compares them with reference to the research results of the domestic and foreign scholars in the velocity analysis method.With the increasing demand for seismic data in production,the use of higher resolution is particularly important,but the conventional velocity analysis method is affected by the window length and the shortcomings of the algorithm itself,resulting in processing the low accuracy of the data,so the demand for new speed analysis methods is increasing.And the velocity analysis method which based on phase correlation statistics can avoid this effect,and the speed of its analysis is more convergent.In this paper,this method is implemented by the program algorithm and the application effect is demonstrated.In addition,the author summarizes and validates the predecessors' analysis and application in this method and proves the feasibility of the method.Finally,we compare the phase correlation statistical velocity analysis method with the conventional method in the case of isotropic media and anisotropic media,and obtain the advantages and disadvantages of the method.Based on the multi-wave anisotropy,this paper demonstrates the application of multi-wave velocity modeling software in practical application by practical seismic data processing,and further validates the velocity analysis theory of anisotropic media.