1887

Abstract

Summary

Conventional velocity model building (VMB) in complex regimes, such as intra and subsalt data, requires time-consuming manual intervention. It is a process that can produce unreliable models, leading to an increase in uncertainty for subsalt lead evaluation. We demonstrate an application of Full Waveform Inversion (FWI) to refine legacy velocity models generated by conventional VMB. We present our solution on a simultaneous long-offsets (SLO) dataset from the Gulf of Mexico, acquired with dual-sensor streamers, which provided low-frequency rich data. The SLO configuration recorded data with 16 km of offset, enabling both refractions and reflections to update the deeper parts of the velocity model. We employ an FWI velocity gradient that eliminates the migration isochrones. This provides support for the intra and subsalt model updates by removing the reflectivity imprint from the updated models. The FWI application successfully refined the geometry of the salt bodies including the base salt and the intrasalt enclosures. RTM images show a marked uplift, particularly for both the salt flanks and subsalt reflectors.

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/content/papers/10.3997/2214-4609.201900056
2019-04-04
2024-04-19
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References

  1. Dellinger, J., Ross, A., Meaux, D., Brenders, A., Gesoff, G., Etgen, J., Naranjo, J., Openshaw, G., Harper, M.
    [2016] Wolfspar, an ‘FWI-friendly’ ultralow-frequency marine seismic source, 86th SEG Annual International Meeting, Expanded abstracts, 4891–4895.
    [Google Scholar]
  2. Long, A., Campbell, S., Fishburn, S., Brandsberg-Dahl, S., Chemingui, N., Dirks, V.
    [2014] No-compromise marine seismic: A full-azimuth survey design for total-wavefield velocity model building and imaging in the deep-water Gulf of Mexico, 84th SEG Annual International Meeting, Expanded abstracts, 52–56.
    [Google Scholar]
  3. Ramos-Martinez, J., Crawley, S., Kelly, S., Tsimelzon, B.
    [2011] Full-waveform inversion by pseudo-analytic extrapolation, 81st SEG Annual International Meeting, Expanded abstracts, 2684–2688.
    [Google Scholar]
  4. Ramos-Martinez, J., Crawley, S., Zou, Z., Valenciano, A.A., Qiu, L. and Chemingui, N.
    [2016] A robust gradient for long wavelength FWI updates, 76th EAGE Conference & Exhibition, Extended Abstracts, Th SRS2 03.
    [Google Scholar]
  5. Shen, X., Ahmed, I., Brenders, A., Dellinger, J., Etgen, J., Michell, S.
    [2017] Salt model building with full-waveform inversion, 87th SEG Annual International Meeting, Expanded abstracts, 1507–1511.
    [Google Scholar]
  6. Sirgue, L., Barkved, O.I., Van Gestel, J.P., Askim, O.J. and Kommedal, J.H.
    [2009] 3D Waveform Inversion on Valhall Wide-azimuth OBC. 71st EAGE Conference and Exhibition, Extended Abstracts, U038.
    [Google Scholar]
  7. Tarantola, A.
    , [1984] Inversion of seismic reflection data in the acoustic approximation, Geophysics, 49, 1259–1266.
    [Google Scholar]
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