High-frequency FWI Imaging: repurposing seismic data for imaging shallow hazards

Dedicated high-resolution site surveys are used to identify potential hazards prior to the placement of infrastructure. Apart from the additional acquisition expense, site surveys are often acquired as a series of 2D lines, which limits their spatial resolution. We describe how FWI Imaging results from existing, raw, conventional 3D seismic data, can be used as a rapidly available 3D alternative or supplementary dataset to help improve understanding of the shallow subsurface. Two case studies demonstrate the potential of this approach. Specifically, they show that high-frequency FWI and associated attributes can help to identify shallow anomalies and fault systems more effectively than standard imaging methods, with a significant increase in resolution. Furthermore, FWI has proven its ability to provide shallow image quality comparable to that of multibeam echo sounder measurements, even with less densely acquired data.