A Half Day Course on
Monitoring and Modelling the Seismic Rock Mass Response to Mining
14 November 2017, RaSiM9, Santiago, Chile
Course presented in English and Spanish
13:00 – 14:00 Introduction to Mine Seismology by Dr. Gerrit Olivier & Dr. Frank Calixto
- What is a seismic event, types of seismic waves, sources of seismic waves, acceleration, velocity and displacement of ground motion (particle velocity) vs. wave speed (propagation velocity).
- Seismic sensors, array configuration.
- Event locations and location errors, velocity calibration, calibration blasts.
- Basic source parameters: origin time and location, Fourier transformation, source spectra, seismic potency, seismic moment, radiated energy, corner frequency and source size.
- Magnitude scales: local magnitudes, moment or potency magnitudes, energy magnitudes.
- Mechanisms of seismic sources in mines: radiation pattern and moment tensor, relation to geology and stress field.
14:00 – 15:30 Seismic Hazard: Intermediate and Short Term Hazard by Dr. Aleksander Mendecki
- Modelling the unexpected, the nature of the power law, Guttenberg-Richter relation and Omori law.
- The upper limit of the next record breaking event in an active mine.
- Record statistics and the upper-truncated potency frequency distribution, the magnitude of the next record breaking event.
- Ground motion hazard.
15:30 – 15:45 Tea/Coffee
15:45 – 16:30 Modelling Seismic Hazard for Mining Scenarios by Dr. Dmitriy Malovichko
- Modelling of seismicity associated with future mining: Salamon-Linkov method, input parameters (in situ stress, failure criteria) and their calibration.
- Assessment of seismic hazard in space: observed and modelled seismicity, effect of size and mechanism of large events, probabilities of occurrence of potentially damaging events for future mining steps.
- Assessment of ground motion hazard in space: Ground Motion Prediction Equation and its uncertainties, near-source ground motion, probabilities of exceedance of Peak Ground Velocity for future mining steps.
- Comparing and testing the forecasts of seismic hazard.
16:30 – 17:15 In-Mine Seismics by Dr Richard Lynch
- Active seismic monitoring: controlled seismic sources, stacking, velocity variations, relation to effective elastic parameters, resolution, maximum range; cave front tracking, pillar condition monitoring, stress monitoring.
- Reflection Seismology: theory, limitations, exploration for new ore bodies and geological discontinuities using sparse seismic arrays with active and passive seismic sources; fracture zone investigations.
17:15 – 18:00 Analysis of Ambient Seismic Noise by Dr Gerrit Olivier
- Stress Changes from Ambient Noise (SCAN): Interferometry, theory, applications to mining: S -wave velocities, stress changes and damage zone evolution in 4D.
- Tailings Dam Monitoring: dam wall failures, sub-surface changes, sensor array, velocity changes – correlation with rainfall, pore pressure changes, damage.