1887

Abstract

Summary

Seismic attenuation can be quantified by quality factor Q. Accurate estimation of Q factor is of great significance in exploration geophysics. Currently, most Q estimation methods are based on plane wave theory and assume that the reflection effect is frequency-independent. In fact, real seismic surveys use localized sources which produce spherical waves rather than plane waves. Thus spherical wave theory can give more precise description of real seismic reflection than plane wave theory. However, spherical wave reflectivity (SWR) is frequency-dependent and the frequency-dependent effect is often neglected. In this paper, we use a two-layer model to illustrate the influence of the frequency-dependence of SWR on seismic attenuation estimation. Tests show that the amplitude spectrum of reflection spherical wave has an obvious frequency shift to low frequency compared with the original wavelet spectrum. The estimated Q value is smaller than the real one due to the frequency-dependent effect of SWR. Thus it is important to consider the influence of frequency-dependent SWR on Q estimation in order to accurately estimate and compensate for attenuation.

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/content/papers/10.3997/2214-4609.201600867
2016-05-31
2020-03-31
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References

  1. Alulaiw, B., Gurevich, B.,
    [2013]. Analytic wavefront curvature correction to plane-wave reflection co efficient for a weak contrast interface, Geophysical Prospecting, 61, 53–63.
    [Google Scholar]
  2. Aki, K. and Richards, P.G.
    [2002] Quantitative seismology: Theory and methods. Vol. 1, W.H. Freeman and Co. W.H. Freeman.
  3. Li, J.N., Wang, S.X., Yuan, S.Y., et al.
    [2015] Frequency-dependent spherical wave reflectivity77th EAGE Conference and Exhibition 2015.
    [Google Scholar]
  4. Quan, Y., Harris, J.M.
    [1997] Seismic attenuation tomography using the frequency shift method. Geophysics, 62(3), 895–905.
    [Google Scholar]
  5. Sams, M., Goldberg, D.
    [1990] The validity of Q estimates from borehole data using spectral ratios. Geophysics, 55(1), 97–101.
    [Google Scholar]
  6. Tonn, R.
    [1991] The determination of the seismic quality factor Q from VSP Data: a comparison of different computational methods. Geophysical Prospecting, 39(1), 1–27.
    [Google Scholar]
  7. Wang, S.D., Yang, D.F., Li, J.N., Song, H.J.
    [2015] Q factor estimation based on the method of logarithmic spectral area difference. Geophysics, 80(6), V157–V171.
    [Google Scholar]
  8. Zhang Ch, J., Ulrychz, T.J.
    [2002] Estimation of quality factors from CMP record. Geophysics, 67(5), 1542–1547.
    [Google Scholar]
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