中文摘要：

层析反演的核心是敏感核函数的求取和旅行时反演方程的建立．在射线理论下，射线追踪技术是计算敏感核函数和旅行时的主要方法，因此初至层析的实现需要有一种可以准确追踪初至波路径的射线追踪方法．本文推导了抛物旅行时插值射线追踪公式，提出了基于抛物旅行时插值的最短路径射线追踪方法．理论模型和实际资料处理结果表明，利用该方法实现初至层析速度建模可行．

英文摘要：

The kernel of tomographic inversion is the solution of sensitive kernel function and the establishing set of travel time equations. Based on the ray theory, ray tracing is the main method to calculate the sensitive kernel function and travel time. Therefore the way to trace first break travel path exactly is needed for first break tomography. In this paper the formula of parabolic travel time interpolation is derived based on the previous research. This paper puts forward the dynamic shortest path ray tracing algorithm using parabolic travel time interpolation. The theoretical model and the real data prove the feasibility of the method, which is used to realize the velocity modeling based on the first break tomography.