Microseismic data — a comparison between routine trigger method and continuous data processing

Over the years there have been several attempts to undertake routine real-time microseismic monitoring of open pit mine slopes. This technique has been commonly used in underground operations to manage induced seismicity and rockburst. However, the microseismic monitoring in open pits is still experimental and further studies are required. In this paper, we analysed the data from MMG Century mine where, in November 2013, a microseismic system was installed in order to monitor a large scale unstable slope. Design of the system and installation of the instruments were performed by the Institute of Mine Seismology. The seismic events were recorded, based both on a triggered scheme and in continuous mode. As part of our research project, data was given to four independent groups to be analysed and provide their own results. One group applied a routine method using the triggered data, manually processed them and made them available for the engineers on site within 10 minutes. The other three groups later reanalysed the data using both triggered and continuous waveform. Our work compared the different results obtained, and highlighted some of the key points engineers should be aware of in the design and implementation of a microseismic system in open pit mines.