Crosswell traveltime tomography in three dimensions

On Crosswell Traveltime Tomography

In this paper, we give a theoretical analysis of the crosswell traveltime tomography. In the single arrival case, we prove that the objective function is smooth, and every critical point is a kinematically correct velocity model. A numerical example is presented to demonstrate the properties we prove and the diierence between traveltime tomography and waveform inversion via the output least squ...

A level-set adjoint-state method for crosswell transmission-reflection traveltime tomography

S U M M A R Y We propose a level-set adjoint-state method for crosswell traveltime tomography using both first-arrival transmission and reflection traveltime data. Since our entire formulation is based on solving eikonal and advection equations on finite-difference meshes, our traveltime tomography strategy is carried out without computing rays explicitly. We incorporate reflection traveltime d...

Global Extrema in Traveltime Tomography

Multiscale traveltime tomography

Nonuniqueness in traveltime tomographic velocity analysis is largely the result of insufficiency in model parameterization. Traditional tomography parameterizes the model with nonoverlapping cells. Such single-scale tomography (SST) from inverting traveltimes only may produce underdeterminacy at places of insufficient ray coverage. To cope with the poor and uneven ray coverage, a multiscale tom...

Seismic Traveltime Tomography 1