Seismic tomography and migration without ray tracing

摘要

Abstract: In this paper, we present a new approach for travel-time tomography in which ray tracing is not required. Analytical expressions for the travel-time between any two points and the slowness in a 2D inhomogeneous medium are obtained by minimizing the difference between the analytical travel-time function and observed travel-times. The analytical functions satisfy the Eikonal equation everywhere in the medium, and hence provide a unique solution for the slowness. The computation of travel-times using the analytical function can be much faster than that using ray tracing for pre-stack migration. Furthermore, the computation can be carried out during the migration which will avoid storing of the travel-time field and increase the efficiency of pre-stack migration.!2