1887
Volume 36 Number 12
  • ISSN: 0263-5046
  • E-ISSN: 1365-2397

Abstract

Abstract

Amplitude versus offset inversion is widely used in reservoir characterization, but its implementation on unconventional reservoirs represents a challenge owing to the subtle changes of elastic parameters that demarcate profitable areas. For this reason, it is important to have an estimation of the uncertainty expected from seismic inversion to improve the interpretation of inverted results. We have implemented a systematic estimation of uncertainty of relative elastic properties obtained by damped least squares inversion of Aki and Richards and Fatti et al. approximations of Zoeppritz’s equation. Well log data of the Vaca Muerta unconventional shale in Argentina was used to generate synthetic angle gathers, varying in terms of asignal-to-noise ratio, range of angle coverage and number of partial angle stacks. The inversion results provide a systematic estimation of the uncertainty of the inverted coefficients. Results show that signal-to-noise ratio and range of angle coverage of the seismic data are key parameters to assess the feasibility of the inversion. In case of characterization based on acoustic impedance, the inverted parameters show good correlation with the model, with these correlation values being predicted by the parameter resolution matrix values.

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2018-12-01
2024-04-24
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References

  1. Aster, R., Borchers, B. and Turber, C.
    [2012]. Parameter estimation and inverse problems. Academic Press, Boston, second edition.
    [Google Scholar]
  2. Avseth, P., Mukerji, T. and MavkoG.
    [2005]. Quantitative Seismic Interpretation: Applying Rock Physics Tools to Reduce Interpretation Risk. Cambridge Press, doi:10.1017/CBO9780511600074.
    https://doi.org/10.1017/CBO9780511600074 [Google Scholar]
  3. Bosch, M., Mukerji, T. and Gonzalez, E.
    [2010]. Seismic inversion for reservoir properties combining statistical rock physics and geostatistics: A review. Geophysics, 75(5), 75A165–75A176, doi:10.1190/1.3478209.
    https://doi.org/10.1190/1.3478209 [Google Scholar]
  4. Castagna, J., Swan, H. and Foster, D.
    [1998]. Framework for AVO gradient and intercept interpretation. Geophysics, 63(3), 948–956, doi:10.1190/1.1444406.
    https://doi.org/10.1190/1.1444406 [Google Scholar]
  5. Castagna, J. and Smith, S.
    [1994]. Comparison of AVO indicators: A modeling study. Geophysics, 59(12), 1849–1855, doi:10.1190/1.1443572.
    https://doi.org/10.1190/1.1443572 [Google Scholar]
  6. Constable, S., Parker, R. and Constable, C.
    [1987]. Occam’s inversion: A practical algorithm for generating smooth models from electromagnetic sounding data. Geophysics, 52(3), 289–300, doi:10.1190/1.1442303.
    https://doi.org/10.1190/1.1442303 [Google Scholar]
  7. Convers, C., Hanitzsch, C., Curia, D., Davis, T. and TuraA.
    [2017]. Elastic parameter estimation for the identification of sweet spots, Vaca Muerta Formation, Neuquén Basin, Argentina. The Leading Edge, 36(11), 948a1–948a8, 948a10. doi:10.1190/tle36110948a1.1.
    https://doi.org/10.1190/tle36110948a1.1 [Google Scholar]
  8. Doyen, P.
    [2007]. Seismic reservoir characterization: An earth modelling perspective. EAGE Publications, The Netherlands, doi:10.3997/9789073781771.
    https://doi.org/10.3997/9789073781771 [Google Scholar]
  9. Fatti, J., Smith, G., Vail, P., Strauss, P. and Levitt, P.
    [1994]. Detection of gas in sandstone reservoirs using AVO analysis: A 3-D seismic case history using the geostack technique. Geophysics, 59(9), 1362–1376, doi:10.1190/1.1443695.
    https://doi.org/10.1190/1.1443695 [Google Scholar]
  10. Hansen, P.
    [2000]. The L-Curve and its Use in the Numerical Treatment of Inverse Problems. Computational Inverse Problems in Electrocardiology. WIT Press, 119–142.
    [Google Scholar]
  11. Kautyian, Ziyisyian A., Späth, F.
    [2017]. Uncertainty Estimation of Inverted Elastic Parameters in Shale Reservoirs - A Case Study of Vaca Muerta Formation. 79th EAGE Conference and Exhibition, doi:10.3997/2214‑4609.201700547.
    https://doi.org/10.3997/2214-4609.201700547 [Google Scholar]
  12. Lu, J., Yang, Z., Wang, Y. and ShiY.
    [2015]. Joint PP and PS AVA seismic inversion using exact Zoeppritz equations. Geophysics, 80(5), 239–250, doi:10.1190/geo2014‑0490.1.
    https://doi.org/10.1190/geo2014-0490.1 [Google Scholar]
  13. Menke, W.
    [2012]. Geophysical Data Analysis: Discrete Inverse Theory. Academic Press, Boston, third edition, doi:10.1016/B978‑0‑12‑397160‑9.00019‑9.
    https://doi.org/10.1016/B978-0-12-397160-9.00019-9 [Google Scholar]
  14. Ostrander, W.
    [1984]. Planewave reflection coefficients for gas sands at nonnormal angles of incidence. Geophysics, 49(10), 1637–1648, doi:10.1190/1.1441571.
    https://doi.org/10.1190/1.1441571 [Google Scholar]
  15. Richards, P. and Frasier, C.
    [1976]. Scattering of elastic waves from depthdependent inhomogeneities. Geophysics, 41(3), 441–458, doi:10.1190/1.1440625.
    https://doi.org/10.1190/1.1440625 [Google Scholar]
  16. Thomas, M., Ball, V., Blangy, J. and Tenorio, L.
    [2016]. Rock-physics relationships between inverted elastic reflectivities. The Leading Edge, 35(5), 438–442, 444-444, doi:10.1190/tle35050438.1.
    https://doi.org/10.1190/tle35050438.1 [Google Scholar]
  17. Wallace, R. and Young, R.
    [1997]. Prestack inversion: An extension of AVO for lithology and hydrocarbon fluid quantification. SEG Technical Program, Expanded Abstracts, 1541–1543, doi:10.1190/1.1885710.
    https://doi.org/10.1190/1.1885710 [Google Scholar]
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