f Seismic Tomography and Migration without Ray Tracing

Usual tomography methods require ray tracing to numerically compote the traveltime in order to estimate, at each iteration of the inversion, the error between the data, i.e. the recorded times, and the computed times out of the current velocity model. Furthermore pre-stack migration also requires intensive traveltime computation to calculate the Green's function, which constitutes a time consuming step for both roversion and migration processes.