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Volume 36 Number 11
  • ISSN: 0263-5046
  • E-ISSN: 1365-2397

Abstract

Abstract

Seismic imaging and reservoir characterization in the Fortuna region, offshore Equatorial Guinea, is beset with various geophysical challenges related to the presence of extensive, but small-scale low-velocity gas pockets, which give rise to significant and cumulative image distortion at target level. This distortion had not been resolved in a vintage 2013 broadband pre-stack depth migration project, as the velocity model was not sufficiently well resolved, but was subsequently addressed successfully in a project conducted using high-resolution non-parametric tomography with improved broadband deghosted data. The primary objective of that subsequent project was to improve the understanding of the internal structure of the Viscata and Fortuna reservoirs, and this objective was met via clearer internal imaging of these reservoir intervals and the overlying gas-charged sediments. The follow-on work considered here deals with the use of full waveform inversion to further delineate small-scale velocity anomalies associated with the highly compartmentalized reservoir units, and also to use the full waveform inversion velocity model as a constraint during acoustic impedance inversion. We compare the results of impedance inversion using both a conventional approach (with the well-log velocities to build the background trend), with a new approach using a trend derived from high-resolution waveform inversion velocities.

EAGE Publications BV
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/content/journals/10.3997/1365-2397.2018006
2018-11-01
2024-04-20

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References

  1. Cobo, Y., Chi, S. and Calderon-Macias, C.
    [2018]. Quantitative interpretation from full-waveform inversion in a deep water GOM dataset.80th annual meeting of the European Association of Exploration Geophysicists, Abstracts.
     [Google Scholar]
  2. Fruehn, J.K., Greenwood, S., Valler, V. and Sekulic, D.
    [2014]. Resolving small-scale near-seabed velocity anomalies using non-parametric autopicking and hybrid tomography.CSEG Recorder, 39 (10), 28–33.
     [Google Scholar]
  3. Fruehn, J.K., Harger, D., Cox, P., Minifie, D., Chigbo, J. and Smith, M.
    [2017]. Imaging buried channel systems under a complex overburden: the Fortuna region, offshore Equatorial Guinea.PESGB Africa Workshop, Abstracts.
     [Google Scholar]
  4. Gardner, G.H.F., Gardner, L.W. and Gregory, A.R.
    [1974]. Formation velocity and density - The diagnostic basics for stratigraphic traps.Geophysics, 39, 770–780.
     [Google Scholar]
  5. Jones, I.F., Singh, J., Cox, P., Warner, M., Hawke, C., Harger, D. and Greenwood, S.
    [2018]. High resolution impedance estimation using refraction and reflection FWI: the Fortuna region, offshore Equatorial Guinea.1st EAGE-PESGB velocities workshop, Abstracts.
     [Google Scholar]
  6. Jones, I.F.
    [2015]. Estimating subsurface parameter fields for seismic migration: velocity model building. In: Grechka, V. and Wapenaar, K. (Eds.) Encyclopedia of Exploration Geophysics. SEG, U1-1-U1-24.
     [Google Scholar]
  7. [2010]. An introduction to velocity model building. EAGE, Houten, The Netherlands.
     [Google Scholar]
  8. Luo, Z., Brittan, J., Fan, D., Mecham, B., Farmer, P. and Martin, G.
    [2014]. Imaging complexity in the earth — Case studies with optimized ray tomography.The Leading Edge, 33 (9), 1016–1022.
     [Google Scholar]
  9. Wang, C., Yingst, D., Farmer, P., Jones, I., Martin, G. and Leveille, J.
    [2017]. Reconstructed full-waveform inversion with the extended source.87th SEG Annual Meeting, Expanded Abstracts, FWI5.1.
     [Google Scholar]
http://instance.metastore.ingenta.com/content/journals/10.3997/1365-2397.2018006
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High-resolution impedance estimation using refraction and reflection FWI constraints: the Fortuna region, offshore Equatorial Guinea
First Break 36, 39 (2018); https://doi.org/10.3997/1365-2397.2018006
/content/journals/10.3997/1365-2397.2018006
/content/journals/10.3997/1365-2397.2018006
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  • Article Type: Research Article

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