ASEG Tech Talk - Multi-parameter FWI imaging: high-resolution imaging directly from raw field data

Title: Multi-parameter FWI imaging: high-resolution imaging directly from raw field data

Presenter: Tom Rayment, Chief Geophysicist, DUG Technology

Date: Tuesday 10th May 2022

Time: 7pm AEST

Registration: https://us02web.zoom.us/webinar/register/WN_CN-_WOEpTemeHTx7FF_gtA

Abstract:

Traditional seismic processing workflows can be extremely time-consuming since subsequent stages are only begun after extensive testing and QC of the current process. This linear approach takes the raw field data and passes it through a plethora of conditioning tools (such as designature, deghosting, demultiple and regularisation) to transform the data into a form that can be imaged by legacy migration algorithms, such as Kirchhoff 3D preSDM.

Full waveform inversion (FWI) imaging is a multi-scattering least-squares approach uses the raw field data to estimate many subsurface parameters, including reflectivity, simultaneously ahead of a conventional processing workflow. Since it is using the primaries, multiples and ghosts during imaging, the result is a set of higher resolution subsurface models but in a fraction of the time of a conventional processing workflow due to the fact that little to no pre-processing is required.

In this presentation we demonstrate an 85 Hz comparison between a conventional processing workflow and a novel FWI imaging technique that utilises an augmented wave equation and an advanced optimisation scheme. The FWI imaging approach is simultaneously inverting for velocity and an intercept-reflectivity vector which is fit for structural and amplitude analysis.