Application of cave-scale rock degradation models in the imaging of the seismogenic zone

Abstract

Microseismic monitoring, the engineering application of earthquake seismology, provides an insight into the location and extent of fracturing induced by the caving process. The spatial characteristics of the observed microseismicity provide valuable validation for the back analysis of the cave process through numerical models (e.g. Pierce et al. 2006, Sainsbury et al., 2008). It also provides a tool for the validation of predictive cave models that aim to forecast the extent and location of the seismogenic zone and the evolution of damaged rock mass properties. A case study is presented using Northparkes Mine microseismic (MS) events located by forwardcalculating Pand S-wave travel times using ray-tracing and wavefront construction techniques through velocity structures that mimic heterogeneity and damage in the rock. By using these models it is expected to get a better resolution of the extent, position and structure of the seismogenic zone. Conversely, the location of high-quality events provides a means to validate the fit of strain models.