1887
Volume 65, Issue 5
  • E-ISSN: 1365-2478

Abstract

ABSTRACT

Shales comprise more than 60% of sedimentary rocks and form natural seals above hydrocarbon reservoirs. Their sealing capacity is also used for storage of nuclear wastes. The world's most important conventional oil and gas reservoirs have their corresponding source rocks in shale. Furthermore, shale oil and shale gas are the most rapidly expanding trends in unconventional oil and gas. Shales are notorious for their strong elastic anisotropy, i.e., so‐called vertical transverse isotropy. This vertical transverse isotropy, characterised by a vertical axis of invariance, is of practical importance as it is required for correct surface seismic data interpretation, seismic to well tie, and amplitude versus offset analysis. A rather classical paradigm makes a clear link between compaction in shales and the alignment of the clay platelets (main constituent of shales). This would imply increasing anisotropy strength with increasing compaction. Our main purpose is to check this prediction on two large databases in shaly formations (more than 800 samples from depths of 0–6 km) by extracting the major trends in the relation between seismic anisotropy and compaction. The statistical analysis of the database shows that the simultaneous increase in density and velocity, a classical compaction signature, is quite weakly correlated with the anisotropy strength. As a consequence, compaction can be excluded as a major cause of seismic anisotropy, at least in shaly formations. Also, the alignment of the clay platelets can explain most of the anisotropy measurements of both databases. Finally, a method for estimating the orientation distribution function of the clay platelets from the measurement of the anisotropy parameters is suggested.

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2017-01-20
2020-09-21
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References

  1. AdelinetM. and RasolofosaonP.N.J.2016. 3D rock physics template for anisotropic formations ‐ Application to the study of shale. 78th EAGE Conference and Exhibition.
    [Google Scholar]
  2. AlkhalifahT. and TsvankinI.1995. Velocity analysis for transversely isotropic media. Geophysics60, 1550–1566.
    [Google Scholar]
  3. AvsethP., MukerjiT. and MavkoG.2005. Quantitative Seismic Interpretation: Applying Rock Physics Tools to Reduce Interpretation Risk. Cambridge University Press.
    [Google Scholar]
  4. AvsethP., MukerjiT., MavkoG. and DvorkinJ.2010. Rock‐physics diagnostics of depositional texture, diagenetic alterations, and reservoir heterogeneity in high‐porosity siliciclastic sediments and rocks — A review of selected models and suggested work flows. Geophysics75(5), A31–A47.
    [Google Scholar]
  5. BachrachR.2011. Elastic and resistivity anisotropy of shale during compaction and diagenesis: joint effective medium modeling and field observations. Geophysics76(6), E175–E186.
    [Google Scholar]
  6. BayukI.O., AmmermanM. and ChesnokovE.M.2007. Elastic moduli of anisotropic clay. Geophysics72(5), D107–D117.
    [Google Scholar]
  7. BeloborodovR., PervukhinaM., LuzinV., Delle PianeC., ClennellM.B., ZandiS.et al. 2016. Compaction of quartz‐kaolinite mixtures: the influence of the pore fluid composition on the development of their microstructure and elastic anisotropy. Marine and Petroleum Geology78, 426–438.
    [Google Scholar]
  8. BourbiéT., CoussyO. and ZinsznerB.1987. Acoustics of Porous Media. Houston, TX: Gulf Publishing Company.
    [Google Scholar]
  9. BrevikI., AhmadiG.R., HattelandT. and RojasM.A.2007. Documentation and quantification of velocity anisotropy in shales using wireline log measurements. The Leading Edge26(3), 272–277.
    [Google Scholar]
  10. CizR. and ShapiroS.A.2009. Stress‐dependent anisotropy in transversely isotropic rocks: comparison between theory and laboratory experiment on shale. Geophysics74(1), D7–D12.
    [Google Scholar]
  11. DewhurstD.N. and SigginsA.F.2006. Impact of fabric, microcracks and stress field on shale anisotropy. Geophysical Journal International165, 135–148.
    [Google Scholar]
  12. DraegeA., JakobsenM. and JohansenT.A.2006. Rock physics modelling of shale diagenesis. Petroleum Geoscience12(1), 49–57.
    [Google Scholar]
  13. GaiserJ.E.1990. Transversely isotropic‐phase velocity analysis from slowness estimates. Journal of Geophysical Research: Solid Earth95(B7), 11241–11254.
    [Google Scholar]
  14. GardnerG.H.F., GardnerL.W. and GregoryA.R.1974. Formation velocity and density ‐ Diagnostic basics for stratigraphic traps. Geophysics39(6), 770–780.
    [Google Scholar]
  15. GrechkaV.2014. Anisotropic Velocity Model Building in Microseismic Monitoring. Geophysical Society of Houston.
    [Google Scholar]
  16. HornbyB.E.1995. The elastic properties of shales. PhD thesis, University of Cambridge, UK.
    [Google Scholar]
  17. HornbyB.E.1998. Experimental laboratory determination of the dynamic elastic properties of wet, drained shales. Journal of Geophysical Research103, 29945–29964.
    [Google Scholar]
  18. HornbyB.E., SchwartzL.M. and HudsonJ.A.1994. Anisotropic effective‐medium modeling of the elastic properties of shales. Geophysics59(10), 1570–1583.
    [Google Scholar]
  19. HorneS.A.2012. Mudrock Anisotropy Database. Available on http://www.rockphysicists.org/data.
  20. JapsenP.1999. Overpressured Cenozoic shale mapped from velocity anomalies relative to a baseline for marine shale, North Sea. Petroleum Geoscience5(4), 321–336.
    [Google Scholar]
  21. JapsenP., MukerjiT. and MavkoG.2007. Constraints on velocity‐depth trends from rock physics models. Geophysical Prospecting55(2), 135–154.
    [Google Scholar]
  22. JohansenT.A., RuudB.O. and JakobsenM.2004. Effect of grain scale alignment on seismic anisotropy and reflectivity of shales. Geophysical Prospecting52, 133–149.
    [Google Scholar]
  23. JonesL.E.A. and WangH.F.1981. Ultrasonic velocities in Cretaceous shales from the Williston Basin. Geophysics46(3), 288–297.
    [Google Scholar]
  24. JoshM., EstebanL., Delle PianeC., SaroutJ., DewhurstD.N. and ClennellM.B.2012. Laboratory characterisation of shale properties. Journal of Petroleum Science and Engineering 88–89, 107–124.
    [Google Scholar]
  25. MilitzerB., WenkH.R., StackhouseS. and StixrudeL.2011. First‐principles calculation of the elastic moduli of sheet silicates and their application to shale anisotropy. American Mineralogist96(1), 125–137.
    [Google Scholar]
  26. NafeJ.E. and DrakeC.L.1960. Physical properties of marine sediments. In: The Sea (ed M.N.Hill ), pp. 794–815. New York, NY: Interscience.
    [Google Scholar]
  27. PervukhinaM. and RasolofosaonP.N.J.2015. Burial/compaction and seismic anisotropy in shaly formations. 77th EAGE Conference and Exhibition incorporating SPE EUROPEC 2015, Madrid, Spain.
    [Google Scholar]
  28. PervukhinaM.
    , GolodoniucP. and DewhurstD.N. 2013. Phenomenological study of seismic anisotropy in shales. 75th EAGE Conference and Exhibition incorporating SPE EUROPEC 2013.
    [Google Scholar]
  29. PervukhinaM., SigginsA.F., DewhurstD.N. and GurevichB.2007. Elastic properties of shales with respect to silt fraction. In: ASEG Extended Abstracts .
  30. PervukhinaM., GurevichB., GolodoniucP. and DewhurstD.N.2011. Parameterization of elastic stress sensitivity in shales. Geophysics76(3), B1–B9.
    [Google Scholar]
  31. PervukhinaM., DewhurstD.N., GurevichB., KuilaU., SigginsA.F., RavenM.et al. 2008. Stress‐dependent elastic properties of shales: measurement and modeling. The Leading Edge27(6), 772–779.
    [Google Scholar]
  32. PervukhinaM., GolodoniucP., GurevichB., ClennellM.B., DewhurstD.N. and Norgard BolasH.M.2015. Prediction of sonic velocities in shale from porosity and clay fraction obtained from logs – A North Sea well case study. Geophysics80(1), D1–10.
    [Google Scholar]
  33. PettijohnF.J.1957. Sedimentary Rocks. New York, NY: Harper and Brothers, 718p.
    [Google Scholar]
  34. ReymentR.A. and SavazziE.1999. Aspects of Multivariate Statistical Analysis in Geology. Amsterdam, The Netherlands: Elsevier, 285p.
    [Google Scholar]
  35. RuudB., JakobsenM. and JohansenT.A.2003. Seismic properties of shales during compaction. 73rd SEG annual international meeting, Expanded Abstracts, 1294–1297.
  36. SaroutJ., Delle PianeC., NadriD., EstebanL. and DewhurstD.N.2015. A robust experimental determination of Thomsen's delta parameter. Geophysics80(1), A19–A24.
    [Google Scholar]
  37. SayersC.2005. Seismic anisotropy of shales. Geophysical Prospecting53, 667–676.
    [Google Scholar]
  38. SayersC.M.1994. The elastic‐anisotropy of shales. Journal of Geophysical Research: Solid Earth99, 767–774.
    [Google Scholar]
  39. SchneiderF., PotdevinJ.L., WolfS. and FailleI.1996. Mechanical and chemical compaction model for sedimentary basin simulators. Tectonophysics263(1), 307–317.
    [Google Scholar]
  40. TarbuckE.J. and LutgensF.K.2002. Earth: An Introduction to Physical Geology. Upper Saddle River, NJ: Prentice Hall, 670p.
    [Google Scholar]
  41. ThomsenL.1986. Weak elastic anisotropy. Geophysics51(10), 1954–1966.
    [Google Scholar]
  42. TiwaryD.K., BayukI.O., VikhorevA.A. and ChesnokovE.M.2009. Comparison of seismic upscaling methods: from sonic to seismic. Geophysics74(2), WA3–WA14.
    [Google Scholar]
  43. VasinR.N., WenkH.R., KanitpanyacharoenW., MatthiesS. and WirthR.2013. Elastic anisotropy modeling of Kimmeridge shale. Journal of Geophysical Research: Solid Earth118(8), 3931–3956.
    [Google Scholar]
  44. VernikL. and NurA.1992. Ultrasonic velocity and anisotropy of hydrocarbon source rocks. Geophysics57(5), 727–735.
    [Google Scholar]
  45. WangZ.2002. Seismic anisotropy in sedimentary rocks, Part 2: Laboratory data. Geophysics67(5), 1423–1440.
    [Google Scholar]
  46. ZinsznerB., MeynierP., CabreraJ. and VolantP.2002. Vitesse des ondes ultrasonores, soniques et sismiques dans les argilites du tunnel de Tournemire. Effet de l'anisotropie et de la fracturation naturelle. Oil and Gas Science and Technology – Revue d'IFP Energies nouvelles57(4), 341–353.
    [Google Scholar]
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  • Article Type: Research Article
Keyword(s): Anisotropy , clay platelets , Compaction , Rock physics and Shale
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