Extending the reach of FWI with reflection data: Potential and challenges
A. Gomes and N. Chazalnoel
Event name: 79th EAGE Conference and Exhibition 2017 - Workshops
Session: WS09 Velocity Model Building - Full Wave vs Kinematic Approaches (FWI vs MVA)
Publication date: 12 June 2017
Info: Abstract, PDF ( 611.56Kb )
Price: € 20
In this work, we present a Reflection FWI (RFWI) workflow to update the velocity model using the low-wavenumber component of the FWI gradient of reflection data, the so-called rabbit ears. This is achieved by alternately using high-wavenumber and low-wavenumber components of the gradient to update density and velocity models, respectively. We apply this method to a deep-water survey on the Mexican side of the Gulf of Mexico. The initial model is obtained after diving wave FWI and deep ray-based tomography. However, some discontinuities remain at the deep Wilcox and Cretaceous events. After RFWI application, we observe a significant improvement in these events, both in the migrated image and gathers. Finally, we discuss our observations on the requirements and limitations of RFWI, such as the poor vertical resolution. Furthermore, we make a parallel between this method, conventional FWI and ray-based tomography, identifying potential improvements for RFWI and discussing how to combine these approaches.