Numerical investigation of the use of hydraulic stimulation to mitigate fault slip risk in deep mines

Authors: Schmidt, ES; Eberhardt, E

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DOI https://doi.org/10.36487/ACG_rep/1704_03_Schmidt

Cite As:
Schmidt, ES & Eberhardt, E 2017, 'Numerical investigation of the use of hydraulic stimulation to mitigate fault slip risk in deep mines', in J Wesseloo (ed.), Deep Mining 2017: Proceedings of the Eighth International Conference on Deep and High Stress Mining, Australian Centre for Geomechanics, Perth, pp. 79-88, https://doi.org/10.36487/ACG_rep/1704_03_Schmidt

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Abstract:
Fault slip and associated seismicity present a significant risk to the safety of underground mines. This paper investigates whether hydraulic stimulation, defined as the injection of pressurised fluid into a rock mass in advance of mining, has the potential to mitigate such risks. Fluid injected in the proximity of a criticallystressed pre-existing fault plane decreases the effective normal stress acting on the fault, initiating slip. Based on this concept, hydraulic stimulation could be used to trigger the release of built-up strain energy in advance of mining. Numerical investigations are carried out in a two-dimensional distinct element code to model the effect of injection on the slip of a pre-existing fault located adjacent to a conceptualised open stope mining operation. Injection is accompanied by slip and a significant decrease in shear stress acting on the fault. When no injection is performed, excavation triggers a series of slip events in response to the changing abutment stresses, generating a maximum Mw 1.3 event. Conversely, when hydraulic injection is performed prior to the mine excavation sequencing, the total number of slip events is reduced, and a lower maximum magnitude of Mw 1.1 is observed. Longer injection durations are observed to trigger larger areas of slip and greater total shear displacements. However, a consequence of injection activities is that stress becomes concentrated outside of the fluid propagation front, potentially triggering seismicity in areas where it was not originally anticipated.

Keywords: fault slip, induced seismicity, hydraulic injection, numerical modelling, rockbursts, shearing

References:
Bewick, RP, Valley, B, Runnalls, S, Whitney, J & Krynicki, Y 2009, ‘Global approach to managing deep mining hazards’, in M Diederichs & G Grasselli (eds), Proceedings of the 3rd CANUS Rock Mechanics Symposium, Toronto.
Blake, W & Hedley, DGF 2003, Rockbursts: Case Studies from North American Hard-Rock Mines, Society for Mining, Metallurgy, and Exploration, Littleton, Colorado.
Board, M, Rorke, T, Williams, G & Gay, N 1992, ‘Fluid injection for rockburst control in deep mining’, in Tillerson & Wawersik (eds), Proceedings of the 33rd US Symposium on Rock Mechanics, Balkema, Rotterdam, pp. 111–120.
Cundall, PA & Lemos, JV 1990, ‘Numerical simulation of fault slip instabilities with a continuously-yielding joint model’, C Fairhurst (ed.), Proceedings of the 2nd International Symposium on Rockbursts and Seismicity in Mines, Balkema, Rotterdam,
pp. 147–152.
Catalan, A, Dunstan, G, Morgan, M, Green, S, Jorquera, M, Thornhill, T, Onederra, I & Chitombo, G 2012, ‘How can an intensive preconditioning concept be implemented at mass mining method? Application to Cadia East panel caving project’, Proceedings of the 46th US Rock Mechanics/Geomechanics Symposium, American Rock Mechanics Association, Alexandria.
Gambino, GF & Harrison, JP 2015, ‘Assessment of unpredictability in hydraulic fracturing for stress amelioration around underground excavations’, in F Hassani, J Hadjigeorgiou & J Archibald (eds), Proceedings of the 13th International Congress of Rock Mechanics, International Society of Rock Mechanics, Lisboa.
Hanks, TC & Kanamori, H 1979, ‘A moment magnitude scale’, Journal of Geophysical Research, vol. 84, no. B5, pp. 2348–2350.
Itasca Consulting Group 2010, UDEC, version 6.0, Itasca Consulting Group, Minneapolis, viewed 25 January 2017, www.itascacg.com/software/udec
Kaiser, PK, Valley, B, Dusseault, MB & Duff, D 2013, ‘Hydraulic fracturing mine back trials — design rationale and project status’, in AP Bunger, J McLennan & R Jeffrey (eds), Proceedings of the International Conference for Effective and Sustainable Hydraulic Fracturing: HF2013, Intech, Rijeka, pp. 877–890.
Malek, F, Espley, S & Yao, M 2008, ‘Management of high stress and seismicity at Vale Inco Creighton Mine’, Proceedings of the 42nd US Rock Mechanics Symposium, American Rock Mechanics Association, Alexandria.
McClure, MW & Horne, RN 2014, ‘An investigation of stimulation mechanisms in Enhanced Geothermal Systems’, International Journal of Rock Mechanics and Mining Sciences, vol. 72, pp. 242–260.
McGarr, A 1994, ‘Some comparisons between mining-induced and laboratory earthquakes’, Pure and Applied Geophysics, vol. 142, no. 3–4, pp. 467–489.
McGarr, A 1999, ‘On relating apparent stress to the stress causing earthquake fault slip’, Journal of Geophysical Research, vol. 104, no. B2, pp. 3003–3011.
Mills, KW, Jeffrey, RG & Zhang, X 2004, ‘Growth analysis and fracture mechanics based on measured stress change near a full-size hydraulic fracture’, in DP Yale, SM Willson & AS Abou-Sayed (eds), Gulf Rocks 2004: Proceedings of the 6th North American Rock Mechanics Symposium, American Rock Mechanics Association, Alexandria.
Preisig, G, Eberhardt, E, Gischig, V, Roche, V, van der Baan, M, Valley, B, Kaiser, PK, Duff, D & Lowther, R 2015, ‘Development of connected permeability in massive crystalline rocks through hydraulic fracture propagation and shearing accompanying fluid injection’, Geofluids, vol. 15, no. 1–2, pp. 321–337.
Snelling, PE, Godin, L & McKinnon, SD 2013, ‘The role of geologic structure and stress in triggering remote seismicity in Creighton Mine, Sudbury, Canada’, International Journal of Rock Mechanics and Mining Sciences, vol. 58, pp. 166–179.
van As, A & Jeffrey, RG 2000, ‘Caving induced by hydraulic fracturing at Northparkes Mines’, in J Girard, M Liebman, C Breeds & T Doe (eds), Pacific Rocks 2000, Balkema, Rotterdam, pp. 353–360.
Warpinski, NR, Mayerhofer, MJ, Vincent, MC, Cipolla, CL & Lolon, EP 2009, ‘Stimulating unconventional reservoirs: Maximizing network growth while optimizing fracture conductivity, Journal of Canadian Petroleum Technology, vol. 48, no. 10, pp. 39–51.
Yao, M, Chinnasane, DR & Harding, D 2009, ‘Mitigation Plans for Mining in Highly Burst-Prone Ground Conditions at Vale Inco Copper Cliff North Mine’, in M Diederichs & G Grasselli (eds), Proceedings of the 3rd CANUS Rock Mechanics Symposium, Canadian Rock Mechanics Association, American Rock Mechanics Association, Alexandria.
Yao, M, Forsythe, A & Chinnasane, DR 2016, ‘De-stress blasting strategy for mining in highly stressed sill pillars at Vale’s Sudbury mines – Two case studies’, Proceedings of Workplace Safety North’s Mining Health and Safety Conference, Workplace Safety North, North Bay.
Zangeneh, N, Eberhardt, E, Bustin, RM & Bustin, A 2013, ‘A numerical investigation of fault slip triggered by hydraulic fracturing’, in AP Bunger, J McLennan & R Jeffrey (eds), Proceedings of the International Conference for Effective and Sustainable Hydraulic Fracturing: HF2013, Intech, Rijeka, pp. 477–488.




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