1887

Abstract

Summary

Elastic reverse time migration (ERTM) is being used for multi-component seismic data to obtain high quality images. However, the final images may suffer from artefacts caused by P- and S-wave crosstalk and some imaging noise caused by the rectangular grid discretization of the irregular seabed interfaces, when applying it on the OBS data from fluid-solid media with irregular seabed interfaces. To overcome the problem, we have developed a separated-wavefield ERTM in the curvilinear system. The first-order acoustic wave equations are transformed into that in the curvilinear system and applied into the fluid part. The P- and S-wave separated wave equation in the curvilinear system is derived and applied into the solid part. New vector imaging conditions are derived in the curvilinear system to obtain images in PP-x, PS-x, SP-x, SS-x, PP-z, PS-z, SP-z and SS-z components. Numerical examples on a layered fluid-solid model with irregular seabed interfaces suggest that the proposed ERTM can get more high quality images than three convention ERTM method with less imaging noise and artefacts.

Loading

Article metrics loading...

/content/papers/10.3997/2214-4609.201800979
2018-06-11
2020-04-05
Loading full text...

Full text loading...

References

  1. Aki, K., and Richards, P.
    , 2002. Quantitative seismology (second edition). University Science Books.
    [Google Scholar]
  2. Nielsen, P., BergP., SkovgaardO.
    , 1994, Using the pseudospectral technique on curved grids for 2D acoustic forward modeling: Geophysical Prospecting, 42, 321–341
    [Google Scholar]
  3. Fornberg, B.
    , 1988, The pseudospectral method: accurate representation of interfaces in elastic wave calculations: Geophysics, 53, 625–637
    [Google Scholar]
  4. Hestholm, S. O., and B. O.Ruud
    , 1994, 2D finite-difference elastic wave modelling including surface topography: Geophysical Prospecting, 42, 371–390
    [Google Scholar]
  5. Qu, Y., Huang, J., Li, Z. et al.
    , 2017, A hybrid grid method in an auxiliary coordinate system for irregular fluid-solid interface modeling. Geophysical Journal International, 208(3), 1540–1556.
    [Google Scholar]
  6. Qu, Y., Li, J., Huang, J., and Li, Z.
    , 2017, Elastic least-squares reverse time migration with velocities and density perturbation. Geophysical Journal International, 202(2), 1033–1056.
    [Google Scholar]
  7. Sun, R., Chow, J., and Chen, K. J.
    , 2001. Phase correction in separating P-and S-waves in elastic data. Geophysics66 (5), 1515–1518.
    [Google Scholar]
  8. Sun, R., McMechan, G. A., and Chuang, H.
    , 2011. Amplitude balancing in separating P- and S-waves in 2D and 3D elastic seismic data. Geophysics76 (3), S103–S113.
    [Google Scholar]
  9. Qu, Y., Li, Z., Huang, J. et al.
    , 2017, Elastic full waveform inversion for surface topography. Geophysics, 82(5), R269–R285.
    [Google Scholar]
  10. , 2017, An elastic full waveform inversion based on wave-mode separation. Exploration Geophysics. 52(4): 422–444.
    [Google Scholar]
  11. Huang, J., Qu, Y., Li, Z. et al.
    , 2015, Variable coordinate system forward modeling method for irregular surface based on dual-variable grid. Applied Geophysics, 12(1): 101–110.
    [Google Scholar]
http://instance.metastore.ingenta.com/content/papers/10.3997/2214-4609.201800979
Loading
/content/papers/10.3997/2214-4609.201800979
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