Full waveform inversion (FWI) serves as a useful tool to quantitatively investigate the properties of the media. One of the biggest challenges is its huge computational cost, especially for the three-dimensional (3D) case. Multisource approach is a helpful method to speed up full waveform inversion, as well as migration. However, current elastic FWI algorithms with simultaneous sources, such as random time series and random polarity methods may be subjected to crosstalk noise, which is a tough problem and affects inversion quality. We develop a novel 3D elastic full waveform inversion method with multisource frequency encoding based on phase sensitive detection (PSD) without the crosstalk. We propagate seismic wavefield excited by the encoded sources with a series of single frequency components. Extracting the wavefield corresponding to each single frequency source by PSD and calculating the total gradients of the objective function with respect to model parameters by summing the gradients of all single frequencies, we can effectively avoid the crosstalk in our multisource FWI algorithm. The numerical examples show that our scheme can effectively separate the wavefield of a single source from the blended wavefields and obtain crosstalk-free inversion results.
Presentation Date: Tuesday, September 17, 2019
Session Start Time: 9:20 AM
Presentation Time: 10:35 AM
Location: Poster Station 10
Presentation Type: Poster