1887
Volume 66, Issue 5
  • E-ISSN: 1365-2478

Abstract

ABSTRACT

Seismic reflection pre‐stack angle gathers can be simultaneously inverted within a joint facies and elastic inversion framework using a hierarchical Bayesian model of elastic properties and categorical classes of rock and fluid properties. The Bayesian prior implicitly supplies low frequency information via a set of multivariate compaction trends for each rock and fluid type, combined with a Markov random field model of lithotypes, which carries abundance and continuity preferences. For the likelihood, we use a simultaneous, multi‐angle, convolutional model, which quantifies the data misfit probability using wavelets and noise levels inferred from well ties. Under Gaussian likelihood and facies‐conditional prior models, the posterior has simple analytic form, and the maximum a‐posteriori inversion problem boils down to a joint categorical/continuous non‐convex optimisation problem. To solve this, a set of alternative, increasingly comprehensive optimisation strategies is described: (i) an expectation–maximisation algorithm using belief propagation, (ii) a globalisation of method (i) using homotopy, and (iii) a discrete space approach using simulated annealing. We find that good‐quality inversion results depend on both sensible, elastically separable facies definitions, modest resolution ambitions, reasonably firm abundance and continuity parameters in the Markov random field, and suitable choice of algorithm. We suggest usually two to three, perhaps four, unknown facies per sample, and usage of the more expensive methods (homotopy or annealing) when the rock types are not strongly distinguished in acoustic impedance. Demonstrations of the technique on pre‐stack depth‐migrated field data from the Exmouth basin show promising agreements with lithological well data, including prediction accuracy improvements of 24% in and twofold in density, in comparison to a standard simultaneous inversion. Much clearer and extensive recovery of the thin Pyxis gas field was evident using stronger coupling in the Markov random field model and use of the homotopy or annealing algorithms.

Loading

Article metrics loading...

/content/journals/10.1111/1365-2478.12625
2018-04-06
2024-04-23
Loading full text...

Full text loading...

References

  1. AkiK. and RichardsP.G.1980. Quantitative Seismology: Theory and Methods. San Francisco: W.H. Freeman and Co.
    [Google Scholar]
  2. BleisteinN., CohenJ.K. and StockwellJ.W.2001. Mathematics of Multidimensional Seismic Imaging, Migration, and Inversion. Springer.
    [Google Scholar]
  3. BulandA., KolbjørnsenO., HaugeR., SkjævelandØ. and DuffautK.2008. Bayesian lithology and fluid prediction from seismic prestack data. Geophysics73(3), C13–C21.
    [Google Scholar]
  4. DellingerJ., RossA., MeauxD., BrendersA., GesoffG., EtgenJ. et al. 2016. Wolfspar, an “FWI‐friendly” ultralow‐frequency marine seismic source. Society of Exploration Geophysicists, 4891–4895.
    [Google Scholar]
  5. EidsvikJ., AvsethP., OmreH., MukerjiT. and MavkoG.2004. Stochastic reservoir characterization using prestack seismic data. Geophysics69(4), 978–993.
    [Google Scholar]
  6. FattiJ.L., SmithG.C., VailP.J., StraussP.J. and LevittP.R.1994. Detection of gas in sandstone reservoirs using AVO analysis; a 3‐d seismic case history using the geostack technique. Geophysics59(9), 1362–1376.
    [Google Scholar]
  7. GunningJ. and GlinskyM.2006. WaveletExtractor: a Bayesian well–tie and wavelet extraction program. Computers and Geosciences32, 681–695.
    [Google Scholar]
  8. GunningJ. and KemperM.2012. Some newer algorithms in joint categorical and continuous inversion problems around seismic data. In Geostatistics Oslo 2012, Vol. 17, pp. 263–273. Springer.
    [Google Scholar]
  9. HuangK.1987. Statistical Mechanics. Wiley.
    [Google Scholar]
  10. KatayamaK. and NarihisaH.2001. Performance of simulated annealing‐based heuristic for the unconstrained binary quadratic programming problem. European Journal of Operational Research, 134(1), 103–119.
    [Google Scholar]
  11. KemperM. and GunningJ.2014. Joint impedance and facies inversion–seismic inversion redefined. First Break32, 89–95.
    [Google Scholar]
  12. KolbjørnsenO., BulandA., HaugeR., RøeP., JullumM., MetcalfeR.W. et al. 2016. Bayesian AVO inversion to rock properties using a local neighborhood in a spatial prior model. The Leading Edge35(5), 431–436.
    [Google Scholar]
  13. LarsenA.L., UlvmoenM., OmreH. and BulandA.2006. Bayesian lithology/fluid prediction and simulation on the basis of a Markov‐chain prior model. Geophysics71(5), R69–R78.
    [Google Scholar]
  14. LongA.S. and ReiserC.Ultra‐low frequency seismic: benefits and solutions. Proceedings of the International Petroleum Technology Conference, IPTC, 2014.
  15. NaeiniE.Z., GunningJ. and WhiteR.2017. Well tie for broadband seismic data. Geophysical Prospecting65(2), 503–522.
    [Google Scholar]
  16. PaigeC.C. and SaundersM.A.1982. LSQR: an algorithm for sparse linear equations and sparse least squares. ACM Transactions on Mathematical Software8, 43–71.
    [Google Scholar]
  17. RimstadK.2012. Spatial mixture modeling based on latent random fields applied to seismic inversion . PhD thesis, NTNU.
  18. SamsM. and CarterD.2017. Stuck between a rock and a reflection: a tutorial on low‐frequency models for seismic inversion. Interpretation5(2), B17–B27.
    [Google Scholar]
  19. SamsM., WestlakeS., ThorpJ. and ZadehE.2016. Willem 3D: reprocessed, inverted, revitalized. The Leading Edge35(1), 22–26.
    [Google Scholar]
  20. SzeliskiR., ZabihR., ScharsteinD., VekslerO., KolmogorovV., AgarwalaA. et al. 2006. A comparative study of energy minimization methods for markov random fields. Computer Vision–ECCV2006, 16–29.
    [Google Scholar]
  21. UlvmoenM. and OmreH.2010. Improved resolution in Bayesian lithology/fluid inversion from prestack seismic data and well observations: part 1 — methodology. Geophysics75(2), R21–R35.
    [Google Scholar]
  22. VirieuxJ. and OpertoS.2009. An overview of full‐waveform inversion in exploration geophysics. Geophysics74(6), WCC1–WCC26.
    [Google Scholar]
  23. WainwrightM.J. and JordanM.I.2008. Graphical models, exponential families, and variational inference. Foundation and Trends in Machine Learning1, 1–305.
    [Google Scholar]
  24. WaldenA.T. and HoskenJ.W.J.1985. An investigation of the spectral properties of primary reflection coefficients. Geophysical Prospecting33(3), 400–435.
    [Google Scholar]
  25. WinklerG.2003. Image Analysis, Random Fields and Markov Chain Monte Carlo Methods: A Mathematical Introduction, 2nd edn. Springer.
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journals/10.1111/1365-2478.12625
Loading
/content/journals/10.1111/1365-2478.12625
Loading

Data & Media loading...

Most Cited This Month Most Cited RSS feed

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