ARTICLE

Estimation of VTI parameters using slowness-polarization inversion of P- and SV-waves

NASER TAMIMI1 ILYA TSVANKIN2 THOMAS L. DAVIS3
Show Less
1 Sigma Cubed (SIGMA3) Inc., Englewood, CO 80112, U.S.A. n.tamimi@sigmacubed.com,
2 Center for Wave Phenomena, Department of Geophysics, Colorado School of Mines, Golden, CO 80401, U.S.A. ilya@mines.edu,
3 Reservoir Characterization Project, Department of Geophysics, Colorado School of Mines, Golden, CO 80401, U.S.A. tdavis@mines.edu,
JSE 2015, 24(5), 455–474;
Submitted: 7 July 2015 | Accepted: 14 August 2015 | Published: 1 November 2015
© 2015 by the Authors. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution -Noncommercial 4.0 International License (CC-by the license) ( https://creativecommons.org/licenses/by-nc/4.0/ )
Abstract

Tamimi, N., Tsvankin, I. and Davis, T.L., 2015. Estimation of VTI parameters using slowness-polarization inversion of P- and SV-waves. Journal of Seismic Exploration, 24: 455-474. Ignoring anisotropy may cause serious distortions in the results of seismic data processing and interpretation. Although P-wave data provide valuable information for estimating anisotropy parameters, important additional constraints can be obtained from shear waves. Here, we present an extension of the slowness-polarization method for VSP data, in which we combine the vertical slownesses and polarization angles of P- and SV-waves. The algorithm is developed for VTI (transversely isotropic with a vertical symmetry axis) media, but it can be generalized for azimuthally anisotropic models. The weak-anisotropy approximation shows that adding SV-wave data generally stabilizes slowness-polarization inversion. In particular, SV-waves improve not only estimation of the anellipticity parameter 7 but also help constrain the coefficient 6, if propagation angles around 45° are available. The proposed technique is applied to a synthetic VSP data set generated using a finite-difference code. This test confirms that including SV-waves yields better inversion results than those obtained solely from P-wave data.

Keywords
VSP
multicomponent
anisotropy
transverse isotropy
polarization
slowness
inversion
References
  1. Alkhalifah, T. and Tsvankin, I., 1995. Velocity analysis for transversely isotropic media.Geophysics, 60: 1550-1566.
  2. Backus, G.E., 1965. Possible form of seismic anisotropy of the upper most mantle under ocean. J.Geophys. Res., 70: 3429-3439.de Parscau, J., 1991. Relationship between phase velocities and polarization in transversely isotopicmedia. Geophysics, 56: 1578-1583.de Parscau, J. and Nicoletis, L., 1990. Tranverse isotropy estimation from multioffset VSPs.
  3. Expanded Abstr., 60th Ann. Internat. SEG Mtg., San Francisco: 1439-1442.
  4. Dewangan, P. and Grechka, V., 2003. Inversion of multicomponent, multiazimuthal, walkaway VSPdata for stiffness tensor. Geophysics, 68: 1022-1031.
  5. Farra, V., 2001. Higher-order perturbation of the phase velocity and polarization of qP and qSwaves in anisotropic media. Geophys. J. Internat., 147: 93-104.
  6. Gaiser, J.E., 1990. Transversely isotropic phase velocity analysis from slowness estimates. J.Geophys. Res., 95: 11241-11254.
  7. Grechka, V., Jorgensen, P. and Lopez, J.L., 2006. Anisotropy estimation from marine 3D VSPdata. Offshore Technol. Conf., Houston: OTC17866.
  8. Grechka, V. and Mateeva, A., 2007. Inversion of P-wave VSP data for local anisotropy: Theoryand case study. Geophysics, 72: D69-D79.
  9. Grechka, V., Mateeva, A., Gentry, C., Jorgensen, P. and Lopez, J.L., 2007. Estimation of seismicanisotropy from P-wave VSP data. The Leading Edge, 26: 756-759.
  10. Horne, S. and Leaney, $., 2000. Short note: Polarization and slowness component inversion for TIanisotropy. Geophys. Prosp., 48: 779-788.
  11. Hsu, K., Schoenberg, M. and Walsh, J., 1991. Anisotropy from polarization and moveout: A casestudy. Expanded Abstr., 61st Ann. Internat. SEG Mtg., Houston: 1526-1529.
  12. Jilek, P., Hornby, B. and Ray, A., 2003. Inversion of 3D VSP P-wave data for local anisotropy:P and SV SLOWNESS-POLARIZATION INVERSION 473
  13. A case study. Expanded Abstr., 73rd Ann. Internat. SEG Mtg., Dallas: 1322-1325.
  14. Miller, D.E. and Spencer, C., 1994. An exact inversion for anisotropic moduli from phase slownessdata. J. Geophys. Res., 99: 21651-21657.
  15. Pevzner, R., Gurevich, B. and Urosevic, M., 2011. Estimation of azimuthal anisotropy from VSPdata using multicomponent S-wave velocity analysis. Geophysics, 76: D1-D9.
  16. PSendik, I. and Gajewski, D., 1998. Polarization, phase velocity, and NMO velocity of qP-wavesin arbitrary weakly anisotropic media. Geophysics, 63: 1754-1766.
  17. Rusmanugroho, H. and McMechan, G.A., 2012a. 3D 9C seismic modeling and inversion ofWeyburn field data. Geophysics, 77: R161-R173.
  18. Rusmanugroho, H. and McMechan, G.A., 2012b. Sensitivity of estimated elastic moduli tocompleteness of wave type, measurement type, and illumination aperture at a receiver inmulticomponent VSP data. Geophysics, 77: R1-R18.
  19. Tsvankin, I., 2012. Seismic signatures and analysis of reflection data in anisotropic media, 3rd Ed.SEG, Tulsa, OK.
  20. Tsvankin, 1. and Grechka, V., 2011. Seismology of azimuthally anisotropic media and seismicfracture characterization. SEG, Tulsa, OK.
  21. White, J.E., Martineau-Nicoletis, L. and Monash, C., 1983. Measured anisotropy in Pierre shale.Geophys. Prosp., 31: 709-725.
Share
Back to top
Journal of Seismic Exploration, Electronic ISSN: 0963-0651 Print ISSN: 0963-0651, Published by AccScience Publishing