Regularized amplitude-versus-angle (AVA) inversion with travel time information

TitleRegularized amplitude-versus-angle (AVA) inversion with travel time information
Publication TypeConference Proceedings
Year of Conference2016
AuthorsLi, Z, Li, YE, Fehler, M, Hu, G
Conference NameSEG

Seismic amplitude-versus-angle (AVA) inversion is a standard approach to estimate elastic properties of the reservoir. Seismic AVA inversion only considers the dynamic information in the seismic data, assuming the kinematic information has been correctly accounted for. In this paper, we propose to constrain the AVA inversion using the kinematic seismic information by defining a three-term objective function with 1) an AVA fitting term, 2) an RMS velocity fitting term, and 3) a prior model fitting term. We investigate the influence of the RMS velocity fitting and the prior model term, which are considered as regularization terms for the AVA inversion. We use higher weights on these regularization terms at the beginning of the iterations. Once the cycle-skipping problem is resolved, the impacts of the RMS velocity and prior model terms are gradually reduced so that the overall misfit function is driven by the angle gather data only. Numerical examples show that the AVA inversion regularized by seismic kinematic information is more robust than conventional methods with respect to noise in the data and error in the initial models.