Impact of Full-azimuth and Long-offset Acquisition on Full Waveform Inversion in Deep Water Gulf of Mexico

FWI produces high-resolution velocity models, but it currently relies primarily on transmitted energy; inverting reflections is more involved because they contain density information. In deep water settings, i.e. the water bottom depth is greater than 1km, near to middle offsets (offsets less than 6km) have reflections as the early arrivals. For most deep water wide azimuth towed streamer (WATS) surveys, with a maximum offset of around 8.5km, only the offsets greater than 6km contain refractions and diving wave energy that are useful for FWI. Additionally, in these WATS acquisitions, the penetration depth of the transmitted energy is restricted by the limited surface offsets, thereby producing velocity updates that are more prone to acquisition-related artifacts. In this case study, we evaluate the benefits of full-azimuth and long offset acquisition for determining the velocities of complex overburden in a deep water region of Gulf of Mexico.