Updating salt model using FWI on WAZ data in the Perdido area: benefits and challenges

In this case study, we discuss the impact of using a not-so-appropriate Wide Azimuth Data (WAZ) data which lacks good usable low frequencies and long offset full azimuth coverage for FWI based model building. We use Time-Lag FWI (TLFWI) demonstrated to be an appropriate algorithm by Zhigang et al 2018. We observe significant uplift in the shallow velocity model and salt overhang definitions at most locations. In this abstract, we discuss the limitations of using WAZ data for FWI and the additional effort to obtain better starting models to overcome the lack of sufficient diving energy and lack of low-frequency signal (<3Hz). We also briefly discuss the uncertainties in the inverted models esp. beyond the penetration depth of transmission waves.