FWI Imaging: Achieving AVA Reflectivity Faster than the Conventional Workflow

Abstract

Summary Many seismic processing and imaging workflows have been developed over the years to attenuate aspects of the recorded wavefield which cannot be properly mapped into the image domain through conventional migration algorithms. These workflows, including techniques such as deghosting, designature, and demultiple, have become extensive and time-consuming to execute due to the linear-like fashion they must be applied. Each stage in the workflow must undergo a range of parameter testing with success judged on a subjective basis. We present the application of a novel multi-parameter full-waveform inversion (FWI) imaging technique as an alternative to the conventional workflow. It uses the raw field data to simultaneously perform model building and least squares imaging with all the recorded reflection wavefield. This approach uses the primaries, multiples, and ghosts to generate standard model parameters (like velocity and anisotropy) and high-resolution true amplitude AVA reflectivity images fit for structural and amplitude analysis faster than the conventional workflow. In this paper, we compare the FWI derived reflectivity-with-angle outputs to that of a standard Kirchhoff preSDM workflow to highlight the suitability of FWI imaging to directly supersede the conventional workflows.