1887

Abstract

Summary

We present a hierarchical strategy of viscoelastic full waveform inversion and its application to a real dataset. We show first that, in synthetic tests, mid-offset and far-offset data are particularly sensitive to attenuation and thus purely elastic waveform inversion can fail to obtain a meaningful model, i.e. simultaneous inversion of both elastic and anelastic parameters is required in order to properly treat reflections and converted waves close to the critical angle. We then apply our viscoelastic inversion scheme to long-offset (15 km) data acquired offshore Sumatra. A previous study using (purely) elastic full waveform inversion using the same data on the Mentawai forearc basin dataset found a low velocity anomaly, which could possibly be interpreted as a gas pocket. We apply, rather, our viscoelastic full waveform inversion strategy to the long offset data. We inverted using refracted waves in combination with a frequency continuation approach. In the later stage of the frequency continuation strategy, we included long-offset reflection data that granted access to the smaller wavelength of the model. We inverted simultaneously for elasticity and anelasticity at every stage of the inversion. The final resolution of the velocity model is increased and the dipping structures are better imaged.

Loading

Article metrics loading...

/content/papers/10.3997/2214-4609.201700795
2017-06-12
2020-01-28
Loading full text...

Full text loading...

References

  1. Belahi, T., Fuji, N., Singh, S. C.
    [2015] Elastic Versus Viscoelastic Full Waveform Inversion of Near-offset and Wide-angle Data in the Presence of Attenuation. 77th EAGE Conference and Exhibition 2015, pp. 1–4
    [Google Scholar]
  2. Belahi, T., Singh, S.C., Fuji, N.
    [2016] Viscoelastic full waveform inversion of sea bottom long offset seismic data in presence of attenuation, 78th EAGE Conference and Exhibition 2016, pp.1–4
    [Google Scholar]
  3. Huot, G., Singh, S.C.
    [2015] Imaging of a large amount of free gas in Sumatra forearc basin using elastic full waveform inversion. 77th EAGE Conference and Exhibition 2015, pp. 1–4
    [Google Scholar]
  4. Kurzmann, A., Przebindowska, A., Kohn, D., Bohlen, T.
    [2013] Acoustic full waveform tomography in the presence of attenuation: a sensitivity analysis. Geophys. J. Int., 195(2), pp. 985–1000
    [Google Scholar]
  5. Fuji, N., Kawai, K., Geller, R.J.
    [2010] A methodology for inversion of broadband seismic waveforms for elastic and anelastic structure and its application to the mantle transition zone beneath the Northwestern Pacific. Phys. Earth Planet. Inter., 180, pp. 118–137.
    [Google Scholar]
  6. Lailly, P.
    [1983] The seismic inverse problem as a sequence of before stack migration. Conference on Inverse Scattering, Theory and Applications, SIAM, Expanded Abstracts, 206–220
    [Google Scholar]
  7. Liu, D.C., Nocedal, J.
    [1989] On the limited memory BFGS method for large scale optimization, Mathematical Programming, 45, pp. 503–528.
    [Google Scholar]
  8. Martin, G. S., Marfurt, K. J., Larsen, S.
    [2002] Marmousi-2: An updated model for the investigation of AVO in structurally complex areas. SEC Technical Program Expanded Abstracts, 21(1), 1979–1982.
    [Google Scholar]
  9. Quintal, B., Steeb, H., Frehner, M., Schmalholz, S. M., Saenger, E. H.
    [2012] Pore fluid effects on S-wave attenuation caused by wave-induced fluid flow. Geophysics, 77(3), L13–L23
    [Google Scholar]
  10. Robertsson, J. O., Blanch, J. O., Symes, W. W.
    [1994] Viscoelastic finite-difference modeling. Geophysics, 59(9)
    [Google Scholar]
  11. Tarantola, A.
    [1988] Theoretical Background for the Inversion of Seismic Waveforms, Including Elasticity and Attenuation. Pure and Applied Geophysics, 128, pp. 365–399
    [Google Scholar]
http://instance.metastore.ingenta.com/content/papers/10.3997/2214-4609.201700795
Loading
/content/papers/10.3997/2214-4609.201700795
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error