1887

Abstract

Summary

Elastic anisotropy in the Earth causes many artifacts in an isotropic seismic processing and interpretation. To date, these issues have been ameliorated by using approximations to the full solutions for wave propagation and reflectivity for special material symmetries. This algorithm has been written to extend these capabilities to the general case of reflectivity from the interface between two anisotropic slabs of arbitrary symmetry and orientation. To achieve this, the algorithm solves for polarization, amplitude and slowness of all the wave modes generated by a plane wave incident to the interface. In the first step, the plane-wave velocities and polarizations of all three orthogonal wave modes are calculated for a given incidence angle. Second, the algorithm determines the reflection and transmission angles of all of the possible scattered modes followed by their respective velocities and polarization vectors. With this information, the algorithm solves system of equations incorporating the imposed boundary conditions to arrive at the scattered wave amplitudes. We have tested this algorithm in some of the most computationally difficult models to ensure there is no energy leakage in the system of calculations. This algorithm could be used in seismic processing, migration, and inversion of seismic data in anisotropic media.

Loading

Article metrics loading...

/content/papers/10.3997/2214-4609.201600713
2016-05-30
2024-04-20
Loading full text...

Full text loading...

References

  1. Bass, J.
    [1995] Elasticity of Minerals, Glasses, and Melts. AGU Reference Shelf.
    [Google Scholar]
  2. Daley, P.F. and Hron, F.
    [1977] Reflection and transmission coefficients for transversely isotropic media. Bulletin of the Seismological Society of America, 67(3), 661–675.
    [Google Scholar]
  3. Malehmir, R. and Schmitt, D.R.
    [2016] An Algorithm to Calculate the Seismic Reflectivity and Transmissivity of General Anisotropic Structures. Computer and Geoscience, (under review).
    [Google Scholar]
  4. Musgrave, M.J.P.
    [1970] Crystal Acoustics: Introduction to the Study of Elastic Waves and Vibrations in Crystals (p. 288). Holden-Day.
    [Google Scholar]
  5. Rokhlin, S., Bolland, T. and Adler, L.
    [1986] Reflection and refraction of elastic waves on a plane interface between two generally anisotropic media. The Journal of the Acoustical Society of America, 79(4), 906–918.
    [Google Scholar]
  6. Rüger, A.
    [1997] P -wave reflection coefficients for transversely isotropic models with vertical and horizontal axis of symmetry. Geophysics, 62(3), 713–722.
    [Google Scholar]
  7. [1998] Variation of P-wave reflectivity with offset and azimuth in anisotropic media. Geophysics, 63(3), 935–947.
    [Google Scholar]
  8. Schmitt, D.R.
    [2015] Seismic Properties. In: Vol. 11: Geophysical Properties of the Near Surface Earth: ‘Treatise on Geophysics’, 2nd Edition, ed. G.Schubert. 44, in press, 2015.
    [Google Scholar]
  9. Thomsen, L.
    [1986] Weak elastic anisotropy. Geophysics, 51(10), 1954–1966.
    [Google Scholar]
  10. Ursin, B. and Haugen, G.
    [1996] Weak-contrast approximation of the elastic scattering matrix in anisotropic media. Pure and Applied Geophysics, 148(3–4).
    [Google Scholar]
http://instance.metastore.ingenta.com/content/papers/10.3997/2214-4609.201600713
Loading
/content/papers/10.3997/2214-4609.201600713
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