An evaluation index for the fracturing effect in shale based on laboratory testing

Original Article

Abstract

It is clear that evaluating the fracturing effect with laboratory tests can shed some light on designing fracturing programs for shale gas exploitation. To evaluate the fracturing effect quantitatively, a series of uniaxial cyclic loading tests on shale were conducted. Based on the experimental results, a damage variable derived from the total axial strains of the loading–unloading cycles was established and introduced into a damage evolution equation to analyze damage evolution in the shale. In the end, a new index for evaluating the fracturing effect, \(C_{AN} '\), was proposed. The results show that \(C_{AN} '\) has a positive correlation with fracture complexity and can be regarded as an effective index to evaluate fracture networks in shale using laboratory tests. In addition, this study demonstrates that the fracturing effect is also related to the angle between the direction in which the load is applied and the shale’s bedding plane. This can provide a useful reference for shale gas exploitation.

Keywords

Fracturing effect Damage variable Damage evolution equation Cyclic loading Shale 

Notes

Acknowledgements

This work was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB10030302). The authors would like to express special thanks to anonymous reviewers and the editor for their constructive comments.

References

  1. Almi S, Maso GD, Toader R (2014) Quasi-static crack growth in hydraulic fracture. Nonlinear Anal 109(12):301–318CrossRefGoogle Scholar
  2. Chen L, Shao JF, Huang HW (2010) Coupled elastoplastic damage modeling of anisotropic rocks. Comput Geotech 37(1–2):187–194CrossRefGoogle Scholar
  3. Desroches J, Detournay E, Lenoach B, Papanastasiou P, Pearson JRA, Thiercelin M, Cheng A (1994) The crack tip region in hydraulic fracturing. Proc R Soc Lond A 447(1929):39–48CrossRefGoogle Scholar
  4. Eberhardt E, Stead D, Stimpson B (1999) Quantifying progressive pre-peak brittle fracture damage in rock during uniaxial compression. Int J Rock Mech Min Sci 36(3):361–380CrossRefGoogle Scholar
  5. Fisher MK, Wright CA, Davidson BM, Goodwin AK, Fielder EO, Buckler WS, Steinsberger NP (2005) Integrating fracture-mapping technologies to improve stimulations in the Barnett shale. In: Proceedings of the SPE/annual technical conference and exhibition, San Antonio, Texas, USAGoogle Scholar
  6. Guo TK, Zhang SC, Ge HK, Wang XQ, Lei X, Xiao B (2015) A new method for evaluation of fracture network formation capacity of rock. Fuel 140:778–787CrossRefGoogle Scholar
  7. Hou B, Chen M, Li ZM, Wang YH, Diao C (2014) Propagation area evaluation of hydraulic fracture networks in shale gas reservoirs. Pet Explor Dev 41(6):833–838CrossRefGoogle Scholar
  8. Johri M, Zoback MD (2013) The evolution of stimulated reservoir volume during hydraulic stimulation of shale gas formations. In: Proceedings of the unconventional resources technology conference, Denver, Colorado, USAGoogle Scholar
  9. Josh M, Esteban L, Delle Piane C, Sarout J, Dewhurst DN, Clennell MB (2012) Laboratory characterisation of shale properties. J Pet Sci Eng 88–89(2):107–124CrossRefGoogle Scholar
  10. Liang C, Jiang ZX, Zhang CM, Guo L, Yang YT, Li J (2014) The shale characteristics and shale gas exploration prospects of the Lower Silurian Longmaxi shale, Sichuan Basin, South China. J Nat Gas Sci Eng 21:636–648CrossRefGoogle Scholar
  11. Liu JX, Yang CH, Mao HJ, Chen XL, Liu YT (2015) Study on crack spreading and evolvement of clay shale based on CT image processing. J Zhejing Univ Technol 43(1):66–72 (in Chinese with English abstract) Google Scholar
  12. Martin CD, Chandler NA (1994) The progressive fracture of Lac du Bonnet granite. Int J Rock Mech Min Sci 31(6):643–659CrossRefGoogle Scholar
  13. Meng Q, Zhang M, Han L, Pu H, Nie T (2016) Effects of acoustic emission and energy evolution of rock specimens under the uniaxial cyclic loading and unloading compression. Rock Mech Rock Eng 49(10):3873–3886CrossRefGoogle Scholar
  14. Nolen-Hoeksema RC, Gordon RB (1987) Optical detection of crack patterns in the opening-mode fracture of marble. Int J Rock Mech Min Sci 24(2):135–144CrossRefGoogle Scholar
  15. Peng RD, Ju Y, Gao F, Xie HP, Wang P (2014) Energy analysis on damage of coal under cyclical triaxial loading and unloading conditions. J China Coal Soc 39(2):245–252Google Scholar
  16. Riahi A, Damjanac B (2013) Numerical study of interaction between hydraulic fracture and discrete fracture network. In: Proceedings of the ISRM/international conference for effective and sustainable hydraulic fracturing, Brisbane, AustraliaGoogle Scholar
  17. Roshan H, Sarmadivaleh M, Iglauer S (2016) Shale fracture surface area measured by tracking exchangeable cations. J Pet Sci Eng 138:97–103CrossRefGoogle Scholar
  18. Sone H, Zoback MD (2013) Mechanical properties of shale-gas reservoir rocks—Part 1: static and dynamic elastic properties and anisotropy. Geophysics 78(5):D381–D392CrossRefGoogle Scholar
  19. Su K, Ghoreychi M, Chanchole S (2000) Experimental study of damage in granite. Geotechnique 50(3):235–241CrossRefGoogle Scholar
  20. Suarez-Rivera R, Burghardt J, Stanchits S, Edelman E, Surdi A (2013) Understanding the effect of rock fabric on fracture complexity for improving completion design and well performance. In: Proceedings of the international petroleum technology conference, Beijing, ChinaGoogle Scholar
  21. Wang Y (2014) Research on the mechanical behavior of rock and soil aggregates based on meso-structural mechanics. Ph.D. Thesis, Beijing: University of Chinese Academy of Sciences (in Chinese with English abstract) Google Scholar
  22. Wang MM (2016) The mechanical and acoustic characteristics in the progressive failure process of Longmaxi formation bedded shale. Ph.D. Thesis, Beijing: University of Chinese Academy of Sciences (in Chinese with English abstract) Google Scholar
  23. Wang YX, Cao P, Yin TB (2011) Simulation research for impact damage fracture evolution of brittle rock plate under impact loading. J Sichuan Univ (Eng Sci Ed) 43(6):85–90 (in Chinese with English abstract) Google Scholar
  24. Wang CY, Yang CH, Heng S, Mao HJ (2015) CT test for evolution of mudstone fractures under compressive load. Rock Soil Mech 36(6):1591–1597 (in Chinese with English abstract) Google Scholar
  25. Wei YL, Yang CH, Guo YT, Liu W, Wang L, Heng S (2015) Experimental investigation on deformation and fracture characteristics of brittle shale with natural cracks under uniaxial cyclic loading. Rock Soil Mech 36(6):1649–1658 (in Chinese with English abstract) Google Scholar
  26. Wu YS, Li X, He JM, Zheng B (2016) Mechanical properties of Longmaxi black organic-rich shale samples from south China under uniaxial and triaxial compression states. Energies 9(12):1088CrossRefGoogle Scholar
  27. Xie HP (1990) Rock and concrete damage mechanics. Jiangsu, China (in Chinese) Google Scholar
  28. Xie HP, Ju Y, Li LY, Peng RD (2008) Energy mechanism of deformation and failure of rock masses. Chin J Rock Mech Eng 27(9):1729–1740 (in Chinese with English abstract) Google Scholar
  29. Xu WY, Thiercelin MJ, Walton IC (2009) Characterization of hydraulically-induced shale fracture network using an analytical/semi-analytical model. In: Proceedings of the SPE/annual technical conference and exhibition, New Orleans, Louisiana, USAGoogle Scholar
  30. Xu D, Hu RL, Gao W, Xia JG (2015) Effects of laminated structure on hydraulic fracture propagation in shale. Pet Explor Dev 42(4):573–579CrossRefGoogle Scholar
  31. Xue L, Qin SQ, Sun Q, Wang YY, Lee ML, Li WC (2014) A study on crack damage stress thresholds of different rock types based on uniaxial compression tests. Rock Mech Rock Eng 47(4):1183–1195CrossRefGoogle Scholar
  32. Yan CL, Deng JG, Cheng YF, Li ML, Feng YC, Li XR (2017) Mechanical properties of gas shale during drilling operations. Rock Mech Rock Eng 50(7):1753–1765CrossRefGoogle Scholar
  33. Yang SQ, Ranjith PG, Huang YH, Yin PF, Jing HW, Gui YL, Yu QL (2015a) Experimental investigation on mechanical damage characteristics of sandstone under triaxial cyclic loading. Geophys J Int 201(2):662–682CrossRefGoogle Scholar
  34. Yang TY, Li X, Zhang DX (2015b) Quantitative dynamic analysis of gas desorption contribution to production in shale gas reservoirs. J Unconv Oil Gas Res 9:18–30CrossRefGoogle Scholar
  35. Zhang ZB, Li X, Yuan WN, He JM, Li GF, Wu YS (2015) Numerical analysis on the optimization of hydraulic fracture networks. Energies 8(10):12061–12079CrossRefGoogle Scholar
  36. Zhou H, Zhang K, Feng XT (2011) Experimental study on progressive yielding of marble. Mater Res Innov 15(sup1):s143–s146CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Key Laboratory of Shale Gas and Geoengineering, Institute of Geology and GeophysicsChinese Academy of SciencesBeijingChina
  2. 2.College of Earth ScienceUniversity of Chinese Academy of SciencesBeijingChina
  3. 3.Institutions of Earth ScienceChinese Academy of SciencesBeijingChina
  4. 4.Institute of GeomechanicsChinese Academy of Geological SciencesBeijingChina

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