【摘要】 在中心射线路径作为唯一已知条件的前提下,利用动力学射线追踪可以方便地实现射线路径上格林函数的计算,但傍轴格林函数则难以计算。高斯束是动力学射线追踪的一个重要应用。在高频假设前提下,本文将高斯束作为源点产生的格林函数,进而实现菲涅尔体地震层析成像中核函数的快速计算,最后应用此方法进行菲涅尔体走时地震层析成像的理论模型试验。与波动方程菲涅尔体走时地震层析成像反演结果的对比表明,在高频假设前提下,基于动力学射线追踪进行菲涅尔体地震层析成像反演是可行的。更多还原

【Abstract】 When only the center raypath is known,dynamic raytracing can be easily used to calculate the Green’s function of the points on the raypath,but hard for those outside the raypath.Gaussian beam is one of the important applications of dynamic raytracing.Under high-frequency assumption,the Gaussian beam is treated as the Green’s function in this paper,through which the sensitivity kernel in Fresnel volume tomography(FVT) can be calculated efficiently.Finally,FVT based on this method is performed on a synthetic data.The comparison of the FVT results with wave equation method indicates that under high-frequency assumption FVT realized by dynamic raytracing can be used in practice.更多还原