An effective multiparameter full-waveform inversion in acoustic anisotropic media

Abstract

Multi-parameter Full Waveform Inversion (FWI) suffers from leakage among different medium properties. Here we discuss a practical multi-parameter FWI solution that minimizes leakage and retrieves the long-wavelength features of the anisotropic earth model. Our algorithm is based on a regularization of the objective function and a specific parameterization of an acoustic Transversely Isotropic (TI) medium consisting of the vertical velocity, and Thomsen parameters epsilon and delta. We show, by using synthetic data, that Total Variation (TV) regularization significantly reduces leakage of the vertical velocity in the epsilon model during the inversion. Finally, we show an application on field data from the Gulf of Mexico where the flatness of the common image gathers is significantly improved.

Waveform Tomography of Two-Dimensional Three-Component Seismic Data for HTI Anisotropic Media

“…One may also choose to balance the differences of different parameters using a tuning factor to make the misfit function decrease along the optimal composite gradient direction (Wang 1998;Gao and Wang 2016). Adding constraints, such as Total Variation regularization, to the misfit function is also helpful for reducing leakage of imprints between different parameters (Ramos-Martínez et al 2017). Meanwhile, proper inversion strategies, such as a multi-scale inversion strategy or inverting one parameter by one parameter sequentially (Waheed et al 2016), are also helpful for multiple parameter inversions.…”