Abstract:As an improved ray migration method,Gaussian beam migration not only inherits the efficiency and flexibility of ray methods,but also has the imaging accuracy close to wave equation migration methods. Compared with traditional Gaussian beam migration in frequency domain,the method in time domain greatly improves computational efficiency by adjusting the imaging formula and converting frequency integral into the function of imaging time. As seismic azimuth becomes larger and recording spread becomes longer,the influence of anisotropy on seismic migration can't be ignored any longer. This paper introduces the anisotropic ray tracing algorithm based on phase velocity to time-domain Gaussian beam migration and optimizes the dynamic ray tracing correlation coefficient,and finally proposes a more efficient method for acoustic anisotropic media. Model tests have demonstrated that the method proposed has higher computational efficiency and better applicability while maintaining higher imaging accuracy than similar anisotropic algorithms,especially it can be used for imaging complex anisotropic structures.
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