Observational studies in South African mines to mitigate seismic risks: a mid-project progress report

Abstract

Mining-induced earthquakes pose a risk to workers in deep mines, while natural earthquakes pose a risk to people living close to plate boundaries and even in stable continental regions. A 5-year Japan-SA collaborative project "Observational studies in South African mines to mitigate seismic risks" was launched in 2010. Here we report on progress since the report at Geosynthesis 2011 in Cape Town. Acoustic emission sensors, accelerometers, strainmeters, and controlled seismic sources have been installed at sites in Cooke, Moab-Khotsong and Sibanye gold mines to monitor the deformation of the rock mass, the accumulation of damage during the earthquake preparation phase, and dynamic stress as the rupture front propagates. These data are being integrated with measurements of stress, stope closure, stope strong motion, and seismic data recorded by the mine-wide network.