Ollila, B 2024, 'Seismic analysis of abutment events at LaRonde 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. 963-980, https://doi.org/10.36487/ACG_repo/2465_61
(https://papers.acg.uwa.edu.au/p/2465_61_Ollila/)
Abstract: The purpose of this paper is to characterise the source mechanisms of two large seismic events (magnitude Nuttli ≥ 3.0) using routine seismic data analysis tools. When there is no clear evidence of source mechanism type, there is a prevailing tendency to attribute fault slip mechanisms to large magnitude seismic events. This study uses seismic source parameter analysis to highlight characteristics of two large events that are more consistent with a stress-driven mechanism than a fault-related failure process.
While fault-related seismicity tends to be confined to the plane of a geologic feature, stress-driven seismicity tends to be controlled by regions of mining-induced stress around mine voids and can migrate as mining progresses. Using seismic data from an ultra-deep open stoping mine in northern Quebec, this study characterises a migrating rock mass failure region in the mine abutments. The locations of seismic events, including mine-scale occurrences, are linked to the advancing stoping front of the mine abutment.
Introducing a novel tool, plane-based time–distance charts, enables the exploration of migrating regions of rock mass yield and facilitates event clustering for source parameter analysis. The self-similarity of the large events with the broader migrating failure region is assessed using the Gutenburg–Richter 
frequency–magnitude relation. This analysis sheds light on the distinctive nature of stress-induced rock mass yield zones, providing insights for seismic hazard assessment in deep mining environments.

Keywords: mine seismicity, mine-scale event, seismic data analysis, underground mining