DOI https://doi.org/10.36487/ACG_repo/2465_09
Cite As:
Koulibaly, AS, Jalbout, A, Saeidi, A, Audet, D, Martel, M, Tremblay, K & Dikonda, R 2024, 'Geoseismic strategy for monitoring seismic hazard at Westwood mine', in P Andrieux & D Cumming-Potvin (eds),
Deep Mining 2024: Proceedings of the 10th International Conference on Deep and High Stress Mining, Australian Centre for Geomechanics, Perth, pp. 219-238,
https://doi.org/10.36487/ACG_repo/2465_09
Abstract:
The Westwood mine features a complex geological environment characterised by a high contrast in geological units of varying competence, faults with different orientations and deformation corridors. This complexity presents significant challenges for mining operations, which results in seismic activity being a well-known major issue. Since the start of operations in 2013 several major seismic events have occurred, leading to health, safety and operational problems, and resulting in the complete shutdown of operations in 2020. To ensure the safe and efficient resumption of activities at the Westwood mine, a geoseismic monitoring strategy has been implemented. This strategy includes a geoseismic characterisation of the rock mass of the mine site, enhancement of the seismic system, regular monitoring of seismicity and the implementation of various seismic analysis methods. Through this strategy several aspects of seismicity are closely monitored, including identification of geological contexts related to major events/rockbursts, assessment of seismic event quality, calculation of the current seismic hazard, monitoring of abnormal seismic activity, seismic response to blasting analysis, assessment of the re-entry protocol and stress monitoring using the seismic response to blasts. Through this geoseismic strategy a better understanding of the seismic behaviour of the Westwood mine has been achieved. Currently some aspects of the seismicity can be anticipated, such as high seismic hazard locations, the probable maximum event magnitude to occur at a particular location and its probability of occurrence. Based on this information an exclusion protocol is implemented during blasting to reduce worker exposure and this information is used as a guideline in the design and reinforcement of the ground support system.
Keywords: mine seismology, seismic hazard, seismic analysis, seismic hazard map
References:
Collins, D & Hosseini, Z 2013, ‘Mine monitoring: harnessing microseismic monitoring’, Mining Magazine, vol. 3, pp. 76–80.
Dubiński, J & Mutke, G 2012, ‘Application of PPV method for the assessment of stability hazard of underground excavations subjected to rock mass tremors’, AGH Journal of Mining and Geoengineering, vol. 36, no. 1, pp. 125–132.
Hadjigeorgiou, J & Karampinos, E 2017, ‘Design tools for squeezing ground conditions in hard rock 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. 693–705,
Harris, PH & Wesseloo, J 2015, mXrap v5, The Australian Centre for Geomechanics, University of Western Australia, Perth.
Hudyma, M 2010, Applied Mine Seismology Concepts and Techniques, technical notes for ENGR.
Hudyma, M, & Potvin, Y 2004, ‘Seismic hazard in Western Australian mines’ Journal of the Southern African Institute of Mining and Metallurgy, vol. 104, No. 5, pp. 265–275.
Morkel, IG, Wesseloo, J & Harris, P 2015, ‘Highlighting and quantifying seismic data quality concerns’, in PM Dight (ed.), FMGM 2015: Proceedings of the Ninth Symposium on Field Measurements in Geomechanics, Australian Centre for Geomechanics, Perth, pp. 539–549,
Morkel, IG, Wesseloo, J & Potvin, Y 2019, ‘The validity of Es/Ep as a source parameter in mining seismology’, in W Joughin (ed.), Deep Mining 2019: Proceedings of the Ninth International Conference on Deep and High Stress Mining, The Southern African Institute of Mining and Metallurgy, Johannesburg, pp. 385–398,
Morkel, IG & Rossi-Rivera, P 2017, ‘The implementation and quantification of the Vallejos and McKinnon re-entry methodology’, 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. 173–181,
Morkel, IG & Wesseloo, J 2017, ‘A technique to determine systematic shifts in microseismic databases’, 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. 105–116,
Potvin, Y, Wesseloo, J, Morkel, G, Tierney, S, Woodward, K & Cuello, D 2019, ‘Seismic Risk Management practices in metalliferous mines’, in W Joughin (ed.), Deep Mining 2019: Proceedings of the Ninth International Conference on Deep and High Stress Mining, The Southern African Institute of Mining and Metallurgy, Johannesburg, pp. 123-132,
Vallejos, JA & McKinnon, SD 2010, ‘Temporal evolution of aftershock sequences for re-entry protocol development in seismically active mines’, in M Van Sint Jan & Y Potvin (eds), Deep Mining 2010: Proceedings of the Fifth International Seminar on Deep and High Stress Mining, Australian Centre for Geomechanics, Perth, pp. 199–214,
Vallejos, J & McKinnon, S 2011, ‘Correlations between mining and seismicity for re-entry protocol development’, International Journal of Rock Mechanics and Mining Sciences, vol. 48, no. 4, pp. 616–625.
Wesseloo, J 2018, ‘The spatial assessment of the current seismic hazard state for hard rock underground mines’, Rock Mechanics and Rock Engineering, vol. 51, no. 6, pp. 1839–1862.
Wesseloo, J 2019, ‘Addressing some misconceptions regarding seismic hazard assessment in mines’, in W Joughin (ed.), Deep Mining 2019: Proceedings of the Ninth International Conference on Deep and High Stress Mining, The Southern African Institute of Mining and Metallurgy, Johannesburg, pp. 267–292,