High-resolution Land Full Waveform Inversion - A Case Study on a Data Set from the Sultanate of Oman
A. Sedova, G.T. Royle, O. Hermant, M. Retailleau and G. Lambaré
Event name: 79th EAGE Conference and Exhibition 2017
Session: FWI II - Case Studies
Publication date: 12 June 2017
Info: Extended abstract, PDF ( 2.74Mb )
Price: € 20
Land full waveform inversion (FWI) is hindered by the presence of surface waves, near-surface heterogeneities, topography, and elastic effects. Broadband and large offset data acquisitions have been developed with the aim of investigating FWI as a tool for velocity model building in land environments. FWI using minimally-processed refractions and diving waves provides an efficient solution to recover long spatial wavelengths in the velocity model. This method has been proposed as a means to enhance standard reflection-based methods. Rather than settle for the recovery of long-to-intermediate spatial wavelengths, we incorporate reflection data in the FWI and move to higher frequencies (up to 13Hz) with the aim of recovering a level of model resolution that is comparable to marine case studies. By incorporating reflection data we recover details such as channels and fault structures and see improved imaging results over conventional migration velocity analysis. We outline a data preprocessing sequence tailored for improving data quality at low frequencies and long offsets and describe the FWI workflow. We show the resolution uplift over refraction-based FWI and compare migrated stacks generated with the standard tomography model to that generated with the high frequency FWI result.