Full-waveform inversion for macro velocity model reconstruction in look-ahead offset vertical seismic profile: Numerical singular value decomposition-based analysis
Full-waveform inversion is currently considered as a potential tool for improving depth-velocity models for areas with complex geology. It is well-known that success of the inversion is very sensitive to the available low-frequency content of the data. In the paper we investigate this issue considering a look-ahead offset vertical seismic profile survey and applying singular value decomposition analysis of a linearized forward map as the main tool. We demonstrate with this technique the difference between the sequential full-waveform inversion strategy and the original time-domain approach proposed in the early 1980s. We emphasize the role of the lowest frequency in the data, which is necessary for reliable velocity model inversion in particular cases. Finally we show the existence of a trade-off between the lowest frequency and a regularization parameter of the inversion procedure. The presented approach may be adapted to answer general questions regarding the quality of data and acquisition system parameters required for feasible full-waveform inversion. (c) 2013 European Association of Geoscientists & Engineers.
