Authors: Morton, E; Villaescusa, E; Thompson, A


Cite As:
Morton, E, Villaescusa, E & Thompson, A 2019, 'Self-similarity in rock fracturing and the behaviour of large-scale faults in the mining environment', in W Joughin (ed.), Proceedings of the Ninth International Conference on Deep and High Stress Mining, The Southern Africa Institute of Mining and Metallurgy, Johannesburg.

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Abstract:
Seismicity and earthquakes are the consequences of rock mass fracturing. Laboratory testing has been used to simulate rock fracturing mechanisms since the 1960s, including by Mogi (1962), Scholz ( 1968), Hardy ( 1972), Hirata, Sato and Iko (1987), Main and Meredith (1989) and Lei et al (1992). These investigations suggest that rock fracturing has similar characteristics on all scales. They also reveal that seismic data contains precursory information that can suggest impending failure. Each of these researchers has used their analysis techniques to investigate large-scale earthquake behaviour; however only limited investigations of mining seismicity have been undertaken to-date. Morton (2019) has investigated almost 700 failures in the mining environment that are specifically related to large-scale faults. The aim of the analysis was to determine if fracturing data patterns recognised in small scale laboratory samples could be recognised in real-life mining data and if so, could be used to identify failure within the mining environment. Various analysis methods were presented. New techniques were developed to select seismic events specific to selected large-scale structures within the mining environment. This enabled the analysis of the behaviour of these individual structures. Analysis was conducted on temporal variations in event rate, spatial correlation length and b-value, magnitude and energy. This paper provides a summary of some of the results determined with the research. Analysis of event rate, magnitude and spatial correlation length are provided within this paper. The analysis method and the trends in the each of these parameters will be presented.

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