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Improvement of Reverse-time Migration using Homogenization of Acoustic Impedance
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  • Journal title : Geophysics and Geophysical Exploration
  • Volume 19, Issue 2,  2016, pp.76-83
  • Publisher : Korean Society of Earth and Exploration Geophysicists
  • DOI : 10.7582/GGE.2016.19.2.076
 Title & Authors
Improvement of Reverse-time Migration using Homogenization of Acoustic Impedance
Lee, Gang Hoon; Pyun, Sukjoon; Park, Yunhui; Cheong, Snons;
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Migration image can be distorted due to reflected waves in the source and receiver wavefields when discontinuities of input velocity model exist in seismic imaging. To remove reflected waves coming from layer interfaces, it is a common practice to smooth the velocity model for migration. If the velocity model is smoothed, however, the subsurface image can be distorted because the velocity changes around interfaces. In this paper, we attempt to minimize the distortion by reducing reflection energy in the source and receiver wavefields through acoustic impedance homogenization. To make acoustic impedance constant, we define fake density model and use it for migration. When the acoustic impedance is constant over all layers, the reflection coefficient at normal incidence becomes zero and the minimized reflection energy results in the improvement of migration result. To verify our algorithm, we implement the reverse-time migration using cell-based finite-difference method. Through numerical examples, we can note that the migration image is improved at the layer interfaces with high velocity contrast, and it shows the marked improvement particularly in the shallow part.
Migration;reflection energy;acoustic impedance;fake density;cell-based finite-difference method;
 Cited by
Alkhalifah, T., 2000, An acoustic wave equation for anisotropic media, Geophysics, 65(4), 1239-1250. crossref(new window)

Aminzadeh, F., Burkhard, N., Long, J., Kunz, T., and Duclos, P., 1996, Three dimensional SEG/EAEG models-an update, The Leading Edge, 15(2), 131-134. crossref(new window)

Baysal, E., Kosloff, D. D., and Sherwood, J. W. C., 1983, Reverse time migration, Geophysics, 48(11), 1514-1524. crossref(new window)

Baysal, E., Kosloff, D. D., and Sherwood, J. W. C., 1984, A two-way nonreflecting wave equation, Geophysics, 49(2), 132-141. crossref(new window)

Chang, W. F., and McMechan, G. A., 1986, Reverse-time migration of offset vertical seismic profiling data using the excitationtime imaging condition, Geophysics, 51(1), 67-84. crossref(new window)

Claerbout, J. F., 1971, Toward a unified theory of reflector mapping, Geophysics, 36(3), 467-481. crossref(new window)

Díaz, E., and Sava, P., 2016, Understanding the reverse time migration backscattering: noise or signal?, Geophysical Prospecting, 64(2), 581-594. crossref(new window)

Du, Q., Gong, X., Zhang, M., Zhu, Y., and Fang, G., 2014, 3D PS-wave imaging with elastic reverse-time migration, Geophysics, 79(5), S173-S184.

Etgen, J., 1986, Pre-stack reverse time migration of shot profiles: Sep-50, 151-170.

Etgen, J., and Brandsberg-Dahl, S., 2009, The pseudo-analytical method: Application of pseudo-Laplacians to acoustic and acoustic anisotropic wave propagation, 79th Annual International Meeting, SEG, Expanded Abstracts, 2552-2556.

Etgen, J., Gray, S. H., and Zhang, Y., 2009, An overview of depth imaging in exploration geophysics, Geophysics, 74(6), WCA5-WCA17. crossref(new window)

Fletcher, R., Du, X., and Fowler, P. J., 2008, A new pseudoacoustic wave equation for TI media, 78th Annual International Meeting, SEG, Expanded Abstracts, 2082-2086.

Gray, S., 2000, Velocity smoothing for depth migration: How much is too much, 70th Annual International Meeting, SEG, Expanded Abstracts, 1055-1058.

Jones, I. F., 2014, Tutorial: migration imaging conditions, First Break, 32(12), 45-55.

Lee, H. Y., Min, D. J., Kwon, B. D., and Yoo, H. S., 2008, Time-Domain Elastic Wave Modeling in Anisotropic Media using Cell-Based Finite-Difference Method, Journal of the Korean Society for Geosystem Engineering, 45(5), 536-545.

Levin, S. A., 1984, Principle of reverse-time migration, Geophysics, 49(5), 581-583. crossref(new window)

Loewenthal, D., and Mufti, I. R., 1983, Reversed time migration in spatial frequency domain, Geophysics, 48(5), 627-635. crossref(new window)

McMechan, G. A., 1983, Migration by extrapolation of timedependent boundary values, Geophysical Prospecting, 31(3), 413-420. crossref(new window)

Min, D. J., Shin, C., and Yoo, H. S., 2004, Free-surface boundary condition in finite-difference elastic wave modeling, Bulletin of the Seismological Society of America, 94(1), 237-250. crossref(new window)

Paffenholz, J., McLain, B., Zaske, J., and Keliher, P. J., 2002, Subsalt multiple attenuation and imaging: Observations from the Sigsbee2B synthetic dataset, 72nd Annual International Meeting, SEG, Expanded Abstracts, 2122-2125.

Park, Y., and Pyun, S., 2013, Application of Effective Regularization to Gradient-based Seismic Full Waveform Inversion using Selective Smoothing Coefficients, Jigu-Mulliwa-Mulli-Tamsa, 16(4), 211-216.

Ravasi, M., Vasconcelos, I., Curtis, A., and Kritski, A., 2015, Vector-acoustic reverse time migration of Volve ocean-bottom cable data set without up/down decomposed wavefields, Geophysics, 80(4), S137-S150. crossref(new window)

Sava, P., and Hill, S. J., 2009, Overview and classification of wavefield seismic imaging methods, The Leading Edge, 28(2), 170-183. crossref(new window)

Sun, R., McMechan, G. A., Lee, C. S., Chow, J., and Chen, C. H., 2006, Prestack scalar reverse-time depth migration of 3D elastic seismic data, Geophysics, 71(5), S199-S207. crossref(new window)

Tang, B., Xu, S., and Zhou, H., 2014, A fast RTM implementation in TTI media, 84th Annual International Meeting, SEG, Expanded Abstracts, 3892-3897.

Versteeg, R. J., 1993, Sensitivity of prestack depth migration to the velocity model, Geophysics, 58(6), 873-882. crossref(new window)

Whitmore, N. D., 1983, Iterative depth migration by backward time propagation, 53th Annual International Meeting, SEG, Expanded Abstracts, 382-385.

Yan, J., and Sava, P., 2008, Isotropic angle-domain elastic reversetime migration, Geophysics, 73(6), S229-S239. crossref(new window)

Yan, R., and Xie, X. B., 2012, An angle-domain imaging condition for elastic reverse time migration and its application to angle gather extraction, Geophysics, 77(5), S105-S115. crossref(new window)

Yoon, K., and Marfurt, K. J., 2006, Reverse-time migration using the poynting vector, Exploration Geophysics, 37(1), 102-107. crossref(new window)

Zhang, H., and Zhang, Y., 2008, Reverse time migration in 3D heterogeneous TTI media, 78th Annual International Meeting, SEG, Expanded Abstracts, 2196-2200.

Zhou, H., Zhang, G., and Bloor, R., 2006, An anisotropic acoustic wave equation for modeling and migration in 2D TTI media, 76th Annual International Meeting, SEG, Expanded Abstracts, 194-198.