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The importance of fracture toughness in the estimation of seismic anisotropy and stress orientation in shale formations

RITESH KUMAR SHARMA SATINDER CHOPRA
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TGS Canada, 250 5th Street SW, Suite 2100, Calgary, Alberta, Canada T2P 0R4,
SamiGeo Consulting Ltd., 9062 Scurfield Drive NW, Calgary, Canada T3L 1W3,
JSE 2021, 30(5), 405–418;
Submitted: 8 June 2020 | Accepted: 20 May 2021 | Published: 1 October 2021
© 2021 by the Authors. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution -Noncommercial 4.0 International License (CC-by the license) ( https://creativecommons.org/licenses/by-nc/4.0/ )
Abstract

Shale resource plays are associated with low permeability, and hence hydraulic fracturing is required for their stimulation and production. The effectiveness of hydraulic fracturing depends on how accurately a horizontal well is placed in the formation of interest. The direction of maximum stress and the magnitude of seismic anisotropy play an important role in the placement of a horizontal well, and effective hydraulic fracture stimulations along its length. Therefore, their estimation from seismic data can provide valuable information. While the source of seismic anisotropy is non-unique, fracture induced anisotropy as well as stress induced anisotropy are considered for an estimation of maximum stress direction and magnitude of seismic anisotropy. In this paper, we first introduce the concept of fracture toughness, which refers to the the ability of a rock to resist fracturing and propagation of pre-existing fractures. We then propose a workflow that uses its azimuthal variation for estimating these two parameters on seismic datasets from the Anadarko Basin. After estimating the maximum stress direction and magnitude of seismic anisotropy the available borehole breakout data as well as microseismic data for area of study are brought into consideration for authenticating the maximum stress direction analysis. The dipole shear logs measured at one well are used to validate the estimation for magnitude of seismic anisotropy.

Keywords
fracture toughness
fracture intensity
anisotropy
stress orientation
shale reservoirs
azimuthal-velocity variation
azimuthal-amplitude variation
maximum-stress
minimum-stress
Woodford
References
  1. Alt, R.C. and Zoback, M.D., 2015. A detailed Oklahoma stress map for inducedseismicity mitigation, Search and Discovery article #70198 accessed athttp://www.searchanddiscovery.com/pdfz/documents/2015/70198alt/ndx_alt.pdf.html on 6th June 2019.
  2. Barry, N., Whittaker, N.R. and Singh, S.G., 1992. Rock Fracture Mechanics Principles
  3. Design and Applications. Elsevier Science Publishers, Amsterdam-New York.
  4. Brown, E., Thomas, R. and Milne, A., 1990. The challenge of completion and stimulatinghorizontal wells: Oilfield Rev., 2(3): 52-64.
  5. Crosby, D.G., Yang, Z. and Rahman, S.S., 1998. Transversely fractured horizontal wells.SPE Ann. Techn. Conf., SPE, 50093.
  6. Eaton, D.W., 2018. Passive Seismic Monitoring of Induced Seismicity. CambridgeUniversity Press, Cambridge.
  7. Gray, D., Anderson, P., Logel, J., Delbecq, F., Schmidt, D. and Schmid, R., 2012.
  8. Estimation of stress and geomechanical properties using 3D seismic data. FirstBreak, 30: 59-68.
  9. Gray, D., Schmidt, D. and Delbecq, F., 2010. Optimize shale gas field development usingstresses and rock strength derived from 3D seismic data. SPE, 137315-MS.
  10. Grechka, V. and Tsvankin, I., 1998. 3D description of normal-moveout in anisotropic,inhomogeneous media. Geophysics., 63: 1079-1092.
  11. Grechka, V., Tsvankin, I. and Cohen, J. K., 1999. Generalized Dix equation and analytictreatment of normal-moveout velocity for anisotropic media, Geoph. Prosp., 47:117-148.
  12. Griffith, A.A., 1920. The phenomena of rupture and flow in solids, Philos. Trans.. Roy.Soc., A 221: 163-198
  13. Griffith, A.A., 1924. The theory of rupture. In: Biezeno, C.G. and Burgers, J.M. (Eds),
  14. Proc. 1st Internat. Congr. Appl. Mech., Delft. Drukkerij J. Waltman Jr.: 54-63.
  15. Hall, S.A., Kendall, JM. and Barkved, O.I., 2002. Fractured reservoir characterizationusing P-wave AVOA analysis of 3D OBC data. The Leading Edge, 21: 777-781.
  16. Hoeksema., R.N., 2013. Elements of hydraulic fracturing. Oilfield Rev., Summer, 25(2):51-52.
  17. Miller, C., Water, G. and Rylander, E., 2011. Evaluation of production log data fromhorizontal wells drilled in organic shales. SPE, 144326.
  18. Miller, C., Rylander, E. and Calvej, J.L., 2010. Detailed rock evaluation and strategicreservoir stimulation planning for optimal production in horizontal gas shalewells. AAPG Internat. Conf., Calgary, AB, Canada.
  19. Miller, C., Hamilton, D., Sturm, S., Waters, G., Taylor, T., Calvez, J.L. and Singh, M.,
  20. Evaluating the impact of mineralogy, natural fractures and in situ stresseson hydraulically induced fracture system geometry in horizontal shale wells. SPE,
  21. Miller, C., Water, G. and Rylander, E., 2011. Evaluation of production log data fromhorizontal wells drilled in organic shales. SPE, 144326.
  22. Plahn, S.V., Nolte, K.G., Thompson, L.G. and Miska, S., 1995. A quantitativeinvestigation of the fracture pump-in/flowback test. SPE Ann. Techn. Conf., SPE
  23. Rocha-Rangel, E., 2011. fracture toughness determinations by means of indentationfracture, nanocomposites with unique properties and applications in medicine andindustry. Cuppoletti, J. (Ed.), ISBN: 978-953-307-351-4, InTech, Available from:https://www.intechopen.com/books/nanocomposites-with-unique-properties-and-applications-in-medicine-and-industry/fracture-toughness-determinations-by-means-of-indentation-fracture.
  24. Riiger, A. and Tsvankin, L, 1997. Using AVO for fracture detection: Analytic basis andpractical solutions. The Leading Edge, 10: 1429-1434.
  25. Sack, R.A., 1946. Extension of Griffith's theory of rupture to three dimensions. Proc.,Phys. Soc. London, 58: 729.
  26. Schoenberg, M., and Sayers, C.M., 1995. Seismic anisotropy of fractured rock.Geophysics, 60: 204-211.
  27. Sierra R., Tran, M. and Abousleiman, Y., 2010. Woodford Shale mechanical propertiesand the impacts of lithofacies. Proc. Symp. on the 44th US Rock Mechanics
  28. Symposium and 5th US-Canada Rock Mechanics Symposium, Salt Lake City,Utah, 27-30 June, ARMA-10-461,10p.
  29. Sharma, R.K., Chopra, S. and Lines, L.R., 2019. Replacing conventional brittlenessindices determination with new attributes employing true hydrofracturingmechanism. Expanded Abstr., 89th Ann. Internat. SEG Mtg., San Antionio, 3235-
  30. Sneddon, I.N., 1946. The distribution of stress in the neighborhood of a crack in anelastic solid. Proc. Roy. Soc.: A, 187: 229.
  31. Sneddon, I.N. and Elliott, H.A., 1946. The opening of a Griffith crack under internalpressure. Quart. Appl. Math., 4: 262.
  32. Singleton, S., 2009. The effects of seismic data conditioning on prestack simultaneousimpedance inversion, The Leading Edge, 28: 772-781.
  33. Weng, X., 1993. Fracture initiation and propagation from deviated wellbores. SPEAnn. Techn. Conf. SPE, 26597.
  34. Yu, G., Zhang, Y. Wang, X., Liang, X., Liu, B., Singleton, S. and Smith, M., 2017.
  35. Seismic data gather conditioning for prestack seismic data inversion. Expanded
  36. Abstr., 87th Ann. Internat. SEG Mtg., Houston: 36, 5074-5078.
  37. Zhang, J., 2016. Comprehensive reservoir characterization of the Woodford shale in partsof Garfield and Kingfisher counties, Oklahoma. M.Sc. thesis, Univ. of Oklahoma.
  38. Zheng, X., 2006. Seismic azimuthal anisotropy and fracture analysis from p-p reflectiondata. Ph.D. thesis, Univ. of Calgary, Calgary.
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Journal of Seismic Exploration, Electronic ISSN: 0963-0651 Print ISSN: 0963-0651, Published by AccScience Publishing