摘要：Elastic full-waveform inversion (FWI) updates high-resolution model parameters by minimizing the residuals of multicomponent seismic records between the field and model data. FWI suffers from the potential to converge to local minima and more serious nonlinearity than acoustic FWI mainly due to the absence of low frequencies in seismograms and the extended model domain (P- and S-velocities). Reflection waveform inversion can relax the nonlinearity by relying on the tomographic components, which can be used to update the low-wavenumber components of the model. Hence, we have developed an elastic reflection traveltime inversion (ERTI) approach to update the low-wavenumber component of the velocity models for the P- and S-waves. In our ERTI algorithm, we took the P- and S-wave impedance perturbations as elastic reflectivity to generate reflections and a weighted crosscorrelation as the misfit function. Moreover, considering the higher wavenumbers (lower velocity value) of the S-wave velocity compared with the P-wave case, optimizing the low-wavenumber components for the S-wave velocity is even more crucial in preventing the elastic FWI from converging to local minima. We have evaluated an equivalent decoupled velocity-stress wave equation to ERTI to reduce the coupling effects of different wave modes and to improve the inversion result of ERTI, especially for the S-wave velocity. The subsequent application on the Sigsbee2A model demonstrates that our ERTI method with the decoupled wave equation can efficiently update the low-wavenumber parts of the model and improve the precision of the S-wave velocity.
© 2018 Society of Exploration Geophysicists.

ISSN号：0016-8033

卷、期、页：v 83,n 5,pR463-R474

发表日期：2018-09-01

期刊分区（SCI为中科院分区）：三区

收录情况：SCI（科学引文索引印刷版）,ESI（基本科学指标数据库）,EI（工程索引）,SCIE（科学引文索引网络版）

发表期刊名称：Geophysics

参与作者：Song, Jianyong,Zhang, Mingqiang

通讯作者：王官超

第一作者：王尚旭,董春晖

论文类型：期刊论文

论文概要：王官超,王尚旭,Song, Jianyong,董春晖,Zhang, Mingqiang，Elastic reflection traveltime inversion with decoupled wave equation，Geophysics，2018，v 83,n 5,pR463-R474

论文题目：Elastic reflection traveltime inversion with decoupled wave equation