An Elastic Full-waveform Inversion Method Based on Wavefield Separation
Z.M. Ren, Y. Liu and M.J. Yu
Event name: 77th EAGE Conference and Exhibition 2015
Session: Full Waveform Inversion VII
Publication date: 01 June 2015
Info: Extended abstract, PDF ( 1Mb )
Price: € 20
Owing to its potential to provide more subsurface model parameters with high accuracy, elastic full waveform inversion (FWI) becomes more attractive than acoustic FWI. However, the coupling of different parameters and wave modes results in more local minima and serious nonlinearity. To improve inversion accuracy, we propose a new elastic FWI method based on the wavenumber-domain wavefield vector decomposition scheme. First, the gradients expressed by separated P- or S-wave are derived. Then, a three-stage inversion strategy is introduced. The nonlinearity and non-uniqueness are mitigated by using the P- and S-wave separation and our hierarchical steps. A synthetic example reveals that our new method can obtain better inversion results than the conventional FWI method.