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Full Wave Traveltime Inversion

Summary Full waveform inversion (FWI) is a strongly non-linearity optimization problem, which suffers from the cycle skipping when the seismic data lack low-frequency components. In this abstract, we propose a wave-equation based full wave travetime inversion method to provide a good initial velocity model for the conventional FWI, which we call it as “full wave traveltime inversion (FWTI)”. During the FWTI process, the full wave traveltime difference between the localized synthetic and observed data was measured by the correlation method. In this case, we just need to measure the traveltime difference in a windowed data without separating the different seismic events. Therefore, the velocity model is perturbed until the full wave traveltime difference between the localized synthetic and observed data converge to the minimum point in the least squares sense. Numerical examples show that the combination of FWTI and FWI is promising to be able to solve the cycle skipping, even the seismic data absence of low-frequency components and the initial velocity model is far from the true model.