1887
Volume 8, Issue 6
  • ISSN: 1569-4445
  • E-ISSN: 1873-0604

Abstract

ABSTRACT

To date, state‐of‐the‐art seismic material parameter estimates from multi‐component sea‐bed seismic data are based on the assumption that the sea‐bed consists of a fully elastic half‐space. In reality, however, the shallow sea‐bed generally consists of soft, unconsolidated sediments that are characterized by strong to very strong seismic attenuation. To explore the potential implications, we apply a state‐of‐the‐art elastic decomposition algorithm to synthetic data for a range of canonical sea‐bed models consisting of a viscoelastic half‐space of varying attenuation. We find that in the presence of strong seismic attenuation, as quantified by ‐values of 10 or less, significant errors arise in the conventional elastic estimation of seismic properties. Tests on synthetic data indicate that these errors can be largely avoided by accounting for the inherent attenuation of the seafloor when estimating the seismic parameters. This can be achieved by replacing the real‐valued expressions for the elastic moduli in the governing equations in the parameter estimation by their complex‐valued viscoelastic equivalents. The practical application of our parameter procedure yields realistic estimates of the elastic seismic material properties of the shallow sea‐bed, while the corresponding ‐estimates seem to be biased towards too low values, particularly for S‐waves. Given that the estimation of inelastic material parameters is notoriously difficult, particularly in the immediate vicinity of the sea‐bed, this is expected to be of interest and importance for civil and ocean engineering purposes.

Loading

Article metrics loading...

/content/journals/10.3997/1873-0604.2010032
2010-07-01
2020-04-07
Loading full text...

Full text loading...

References

  1. AmundsenL. and ReitanA.1995Decomposition of multicomponent sea‐floor data into upgoing and downgoing P‐ and S‐waves.Geophysics60, 563–572.
    [Google Scholar]
  2. AyresA. and TheilenF.2001. Preliminary laboratory investigations into the attenuation of compressional and shear waves on near‐surface marine sediments.Geophysical Prospecting49, 120–127.
    [Google Scholar]
  3. BaronL. and HolligerK.2010. Poro‐elastic analysis of the velocity dispersion and attenuation behavior of multi‐frequency sonic logs. In: Advances in Near‐Surface Seismology and Ground‐Penetrating Radar (eds R.Miller , J.Bradford and K.Holliger ), in press. Society of Exploration Geophysicists.
    [Google Scholar]
  4. BartonN.2006. Rock Quality, Seismic Velocity, Attenuation and Anisotropy.Taylor & Francis.
    [Google Scholar]
  5. BestA.I., HuggettQ.J. and HarrisA.J.K.2001. Comparison of in situ and laboratory acoustic measurements on Lough Hyne marine sediments.Journal of the Acoustical Society of America110, 695–709.
    [Google Scholar]
  6. BlanchJ.O., RobertssonJ.O.A. and SymesW.W.1995. Modeling of a constant Q: Methodology and algorithm for an efficient and optimally inexpensive viscoelastic technique.Geophysics60, 176–184.
    [Google Scholar]
  7. BourbiéT., CoussyO. and ZinszerB.1987. Acoustics of Porous Media.Editions Technip.
    [Google Scholar]
  8. BowlesF.A.1997. Observations on attenuation and shear‐wave velocity in fine‐grained, marine sediments.Journal of the Acoustical Society of America101, 3385–3397.
    [Google Scholar]
  9. CaldwellJ.1999. Marine multicomponent seismology.The Leading Edge18, 1274–1282.
    [Google Scholar]
  10. CarcioneJ.M.2001. Wave Fields in Real Media: Wave Propagation in Anisotropic, Anelastic and Porous Media.Pergamon Press.
    [Google Scholar]
  11. EdmeP. and SinghS.C.2008. Receiver function method in reflection seismology.Geophysical Prospecting56, 327–340.
    [Google Scholar]
  12. EdmeP. and SinghS.C.2009. Receiver function decomposition of OBC data: Theory.Geophysical Journal International177, 966–977.
    [Google Scholar]
  13. HamiltonE.L.1980. Geoacoustic modeling of the sea‐floor.Journal of the Acoustical Society of America68, 1313–1340.
    [Google Scholar]
  14. JacksonD.R. and RichardsonM.D.2007. High‐frequency Seafloor Acoustics. Springer. KlimentosT. 1995. Attenuation of P‐ and S‐waves as a method of distinguishing gas and condensate from oil and water.Geophysics60, 447–458.
    [Google Scholar]
  15. LevanderA.R.1988. Fourth‐order finite difference P‐SV seismograms.Geophysics53, 1425–1436.
    [Google Scholar]
  16. MalagniniL.1996. Velocity and attenuation structure of very shallow soils: Evidence for a frequency‐dependent Q.Bulletin of the Seismological Society of America86, 1471–1486.
    [Google Scholar]
  17. MavkoG., MukerjiZ. and DvorkingJ.2009. The Rock Physics Handbook: Tools for Seismic Analysis in Porous Media.Cambridge University Press.
    [Google Scholar]
  18. MuijsR.2005. Wavefield decomposition and imaging of multicomponent seabed seismic data. Unpublished PhD thesis, ETH Zurich.
    [Google Scholar]
  19. MuijsR., RobertssonJ.O.A., CurtisA. and HolligerK.2003. Near‐surface seismic properties for elastic wavefield decomposition: Estimates based on multicomponent land and seabed recordings.Geophysics68, 2073–2081.
    [Google Scholar]
  20. MuijsR., RobertssonJ.O.A. and HolligerK.2004. Data‐driven adaptive decomposition of multicomponent seabed recordings.Geophysics69, 1329–337.
    [Google Scholar]
  21. MuijsR., RobertssonJ.O.A. and HolligerK.2007. Data‐driven adaptive decomposition of multi‐component seabed seismic recordings: Application to shallow‐water data.Geophysics72, V133–V142.
    [Google Scholar]
  22. RobertssonJ.O.A., BlanchJ.O. and SymesW.W.1994. Viscoelastic finite‐difference modeling.Geophysics59, 1444–1456.
    [Google Scholar]
  23. SchalkwijkK.M., WapenaarC.P.A. and VerschuurD.J.1999. Application of two‐step decomposition to multicomponent ocean‐bottom data: Theory and case study.Journal of Seismic Exploration8, 261–278.
    [Google Scholar]
  24. SchalkwijkK.M., WapenaarC.P.A. and VerschuurD.J.2003. Adaptive decomposition of multicomponent ocean‐bottom seismic data into downgoing and upgoing P‐ and S‐waves.Geophysics68, 1091–1102.
    [Google Scholar]
  25. SchoenJ.H.2004. Physical Properties of Rocks: Fundamentals and Principles of Petrophysics.Elsevier.
    [Google Scholar]
  26. WapenaarC.P.A., HerrmannP., VerschuurD.J. and BerkhoutA.J.1990. Decomposition of multicomponent seismic data into primary P‐ and S‐wave responses.Geophysical Prospecting38, 633–662.
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journals/10.3997/1873-0604.2010032
Loading
/content/journals/10.3997/1873-0604.2010032
Loading

Data & Media loading...

  • Article Type: Research Article
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