Information from the test triggers and system log-files are used to monitor and report on the health of the seismic system. The test triggers confirm whether components of the sites are working, and can give information regarding noise on the sensor cables. The system log-files monitor the power and communication efficiencies of the seismometers, as well as the time synchronisation between seismometers.
Some aspects of the system performance are evaluated using seismic data. Specific analysis of the routinely-processed events makes it possible to quantify the following characteristics of individual sites:
- triggering performance, which is the ratio of events recorded by a particular site to the events expected to be recorded by that site (with reference to triggering of other sites and the theoretical ground-motion relation)
- level and frequency content of background seismic noise
- checking the orientation of the sensor using the average misfit between recorded and expected direction of ground motion in P-waves
- site amplification/suppression effects, where the spectra of observed signals in P- and S-waves and corresponding theoretical spectra (obtained using a standard Brune model of the source spectra) are compared
ROUTINE SEISMOLOGICAL REPORTING
Seismic Monitoring Routine Reporting
A summary report on the results of the seismic monitoring is automatically generated on a daily, weekly or monthly basis. Many varied and custom reports can be automatically generated. Some of the common reports:
- Night Shift (NS) and Early Morning Shift (MS) reports: Provide a summary of the seismic activity on the mine, and can notify the standby seismologist of possible hazardous mining regions
- Plot and Listing reports: Display the large events in relation to the mining layout as well as their source parameters
- Seismic-event statistics reports: Summarise the number events recorded per hour and their processing. For example. The number of accepted events, number of rejected events, etc.