Multiparameter FWI of 3D OBC Dataset From the Valhall Field
N. Kamath, R. Brossier, L. Metivier and P. Yang
Event name: 81st EAGE Conference and Exhibition 2019
Session: FWI Case Studies II
Publication date: 03 June 2019
Info: Extended abstract, PDF ( 1.11Mb )
Price: € 20
Full-waveform inversion (FWI) performed in areas with known attenuation can yield distorted velocities when viscous effects are not taken into account. Monoparameter (velocity-only) visco- acoustic FWI using a crude attenuation (Qp ) model can improve the estimated velocity. However, joint inversion to update both velocity and attenuation is ideal, as the obtained Qp can be used for migrating the data. We invert the pressure component of ocean bottom cable (OBC) data acquired in the Valhall field for P-wave vertical velocity VP0 and attenuation Qp . A data subsampling strategy is employed to ensure efficient use of computational resources. Simultaneous inversion of VP0 and Qp results in velocities larger than when the medium is considered acoustic. However, the difference in the velocities obtained from joint inversion and monoparameter visco-acoustic inversion is not significant.