DOWNLOAD POSTER PDFLeast-squares waveform inversion is approved to be capable of reconstructing remarkably detailed models of subsurface structure. Unlike conventional tomography or migration techniques that only make use of specific portion of the seismic data, seismic waveform inversion takes into account essentially any physics of seismic wave propagation that can be modelled. However, without extremely low frequency data or good initial model that contains the long-scale structure information, seismic waveform inversion is very likely to be trapped by numerous spurious local minima. The extended modelling concept combines the global convergence of migration velocity analysis with the physical fidelity of waveform inversion by adding additional dimension of freedom. Using Claerbout’s survey-sinking concept, this study implements depth-oriented extended inversion by introducing a subsurface shift in the imaging condition. Synthetic experiment result demonstrates that the depth-oriented extended waveform inversion can overcome the local minima problem and successfully estimate the true velocity model by using conventional seismic field data.
