1887
Volume 52, Issue 2
  • ISSN: 0812-3985
  • E-ISSN: 1834-7533

Abstract

When implementing reverse-time migration (RTM), reflected waves that are generated during migration may produce false reflectors. One effective method to remove these artefacts is to apply a de-primary RTM algorithm. This de-primary RTM algorithm uses the Hilbert transform to remove RTM artefacts without explicitly separating wavefields. However, multiply reflected down-going waves, such as surface-related multiples and internal multiples that are generated when simulating source and receiver wavefields, are not excluded during cross-correlation even if we adopt the de-primary RTM technique. Therefore, these down-going multiples may produce troublesome RTM artefacts. In this paper, we attempt to reduce these RTM artefacts by combining the de-primary RTM and impedance-matching techniques. Impedance-matching is only effective for normal incidence, so we also apply an absorbing boundary condition to the free surface to remove surface-related multiples. We evaluate the proposed method through the SEG/EAGE salt model. These numerical examples show that the proposed method effectively reduces RTM artefacts and provides clear migration images.

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2021-03-04
2026-01-22
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References

  1. Aminzadeh, F., N.Burkhard, J.Long, T.Kunz, and P.Duclos. 1996. Three dimensional SEG/EAGE models – an update. The Leading Edge15, no. 2: 131–4.
    [Google Scholar]
  2. Baysal, E., D.D.Kosloff, and J.W.C.Sherwood. 1983. Reverse-time migration. Geophysics48, no. 11: 1514–24.
    [Google Scholar]
  3. Baysal, E., D.D.Kosloff, and J.W.C.Sherwood. 1984. A two-way nonreflecting wave equation. Geophysics49, no. 2: 132–41.
    [Google Scholar]
  4. Chattopadhyay, S., and G.A.McMechan. 2008. Imaging conditions for prestack reverse-time migration. Geophysics73, no. 3: S81–9.
    [Google Scholar]
  5. Claerbout, J.F.1971. Toward a unified theory of reflector mapping. Geophysics59, no. 3: 467–81.
    [Google Scholar]
  6. Diaz, E., and P.Sava. 2016. Understanding the reverse time migration backscattering: noise or signal?Geophysical Prospecting64, no. 3: 581–94.
    [Google Scholar]
  7. Etienne, R.2016. EAGE E-lecture. Reverse time migration: How does it work, when to use it. Youtube. https://youtu.be/ywdML8ndYeQ.
  8. Fei, T.W., Y.Luo, and G.T.Schuster. 2010. De-blending reverse-time migration. Expanded abstract. In SEG 80th annual international meeting, 3130–4.
  9. Fei, T.W., Y.Luo, J.Yang, H.Liu, and F.Qin. 2015. Removing false images in reverse time migration: The concept of de-primary. Geophysics80, no. 6: S237–44.
    [Google Scholar]
  10. Fletcher, R.P., P.J.Fowler, P.Kitchenside, and U.Albertin. 2006. Suppressing unwanted internal reflections in prestack reverse-time migration. Geophysics71, no. 6: E79–82.
    [Google Scholar]
  11. Gardner, G.H.F., L.W.Gardner, and A.R.Gregory. 1974. Formation velocity and density – The diagnostic basics for stratigraphic traps. Geophysics39, no. 6: 770–80.
    [Google Scholar]
  12. Jones, I.F.2014. Tutorial: Migration imaging conditions. First Break32, no. 12: 45–55.
    [Google Scholar]
  13. Kaelin, B., and A.Guitton. 2006. Imaging condition for reverse time migration. Expanded abstract. In SEG 70th annual international meeting, 2594–8.
  14. Lee, G.H., S.Pyun, Y.Park, and S.Cheong. 2016. Improvement of reverse-time migration using homogenization of acoustic impedance. [In Korean.] Geophysics and Geophysical Exploration19, no. 2: 76–83.
    [Google Scholar]
  15. Lee, G., and S.Pyun. 2018. Reverse-time migration using surface-related multiples. [In Korean.] Geophysics and Geophysical Exploration21, no. 1: 41–53.
    [Google Scholar]
  16. McMechan, G.A., and W.F.Chang. 1990. 3D acoustic prestack reverse-time migration. Geophysical Prospecting38, no. 7: 737–56.
    [Google Scholar]
  17. Sava, P., and S.J.Hill. 2009. Overview and classification of wavefield seismic imaging methods. The Leading Edge28, no. 2: 170–83.
    [Google Scholar]
  18. Whitmore, N.D.1983. Iterative depth migration by backward time propagation. Expanded abstract. In SEG 53rd annual international meeting, 827–30.
  19. Whitmore, N.D., and L.R.Lines. 1986. Vertical seismic profiling depth migration of a salt dome flank. Geophysics51, no. 5: 1087–109.
    [Google Scholar]
  20. Yoon, K., and K.J.Marfurt. 2006. Reverse-time migration using the Poynting vector. Exploration Geophysics37, no. 1: 102–7.
    [Google Scholar]
  21. Zhang, Y., and J.Sun. 2009. Practical issues in reverse time migration: True amplitude gathers, noise removal and harmonic source encoding. First Break27, no. 1: 53–9.
    [Google Scholar]
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