The spatial and temporal assessment of clustered and time-dependent seismic responses to mining

The phenomenon of seismicity is observed in many hard rock underground mines around the world. The potential for seismic events to damage underground excavations can create a significant hazard to mining personnel, equipment, and infrastructure. The management of seismic hazard is an essential component in minimising the political, social, and economic risks associated with mining. The effective management of seismic hazard is underpinned by a sufficient understanding of the magnitude, spatial, and temporal characteristics of seismicity. These characteristics of seismicity are controlled by causative seismic source mechanisms within a mine and are related to stress conditions, rock mass strength, excavations, geology, and geological features. This paper considers spatially clustered seismicity, which is generated by a timedependent rock mass failure process. Seismicity of this nature is routinely observed following blasting or large seismic events and is referred to as a ‘seismic response’ within this paper. There are numerous interrelated factors that can influence the characteristics of seismic responses and this makes it difficult to establish meaningful correlations with causative processes. Furthermore, the management of seismic response hazard has the tendency to rely on the sitespecific experience, which has inherent limitations. These areas of research can be partly addressed by the quantification of seismic responses that allows for the development of an objective understanding of seismic response hazard. This paper presents a general outline of a recently published methodology for the assessment of seismic responses that concurrently examines the spatial and temporal characteristics of these responses. A general discussion on the major considerations when applying the method is provided in this paper. The benefits of the quantification of seismic responses are illustrated by several case studies. These studies assess individual responses and consider the historical distribution of response characteristics for a mining environment.