Mining induced seismicity

This suite of apps was developed as part of the ACG’s Mine Seismicity and Rockburst Risk Management projects consisting of a suite of apps which provides tools for the analysis and interpretation of mining induced seismicity and the management of seismic hazard.

General analysis app

 

 

 

General analysis app

Principal Author: Johan Wesseloo Other Contributors: Paul Harris, Dan Cumming-Potvin, Kyle Woodward, Gerhard Morkel, Wei Duan, Stuart Tierney

Citation: Wesseloo, J., Harris, P.C., Cumming-Potvin, D., Woodward, K.R., Morkel, I.G., Duan, W. and Tierney S.T. (2015) mXrap software app, Mining Induced Seismicity – General Analysis v1. Perth, Western Australia: The Australian Centre for Geomechanics, The University of Western Australia. http://www.mXrap.com.

Description:  The General Analysis App provides tools for the general analysis of mine induced seismicity. These tools include combinations of complex spatial and range filters, charts, tables and 3D views.

 

  • 3D Display of data

Grid based analysis

Grid based analysis

Principal Authors: Johan Wesseloo and Paul Harris

Citation: Wesseloo, J. and Harris, P.C (2015) mXrap software app, Mining Induced Seismicity – Grid Based Analysis v1. Perth, Western Australia: The Australian Centre for Geomechanics, The University of Western Australia. https//:www.mXrap.com

Description:  The grid-based analysis app provides the tools to evaluate the spatial distribution of seismic source parameters. Based on specified input parameters, a 3-Dimentional spatial kernel interpolation is performed to assess the mean value of seismic source parameters on a given grid. Cumulative source parameters like cumulative apparent volume are assessed through a variable bandwidth kernel interpolation of which the bandwidth is a function of the source size. The b-value is evaluated by implementing a robust algorithm for finding the magnitude of completeness and b-value pair for each grid point.

Post-processing includes the three-dimensional display of results using colour, transparency and gridpoint scaling. Filtering of gridpoints and the events contained in the volumes represented by the gridpoints can be performed. This grid based event filter can also be used for general analysis.

Further reading: Wesseloo, J. (2014) Evaluation of the spatial variation of the b-value. J. S. Afr. Inst. Min. Metall. October 2014.

Wesseloo, J., Woodward, K.R. and Pereira, J. (2014) Grid-based analysis of seismic data. J. S. Afr. Inst. Min. Metall. October 2014.

Plane fitting app

 

 

 

Plane fitting app

Principal Authors: Dan Cumming-Potvin, Kyle Woodward

Other Contributors: Paul Harris, Johan Wesseloo

Citation: Cumming-Potvin, D., Woodward, K.R., Harris, P.C. and Wesseloo, J (2015) mXrap software app, Mining Induced Seismicity – Plane Fitting, version 1. Perth, Western Australia: The Australian Centre for Geomechanics, The University of Western Australia. https//:www.mXrap.com

Description: The plane fitting app provides a tool for fitting a plane through selected seismic events. The app performs Principal Component Analysis (PCA) on the spatial data provided and generates a plane normal to the minor axis with the extent determined by the major and intermediate axis.

A stereo net is provided showing the pole of the plane from the PCA. Planes are also fitted through three-event combinations of the selected events. The pole distribution of these planes is shown as contours on the stereo net. A goodness of fit analysis is performed and a simplified ranking assigned to the best-fit plane.

The plane can be exported as a *.pnt file for later re-use in a “distance to” filter or for display in other apps and programs.

Fit plane though selected seismic events

Fit plane though selected seismic events

Hazard assessment

Hazard assessment

Principal Authors: Johan Wesseloo, Paul Harris

Other Contributors: Gerhard Morkel

Citation: Wesseloo, J. and Harris, P.C, Morkel, I.G. (2015). mXrap software app, Mining Induced Seismicity – Grid Based Hazard Assessment App v1. Perth, Western Australia: The Australian Centre for Geomechanics, University of Western Australia. https//:www.mXrap.com

Description: The grid-based seismic hazard assessment app assesses the current seismic hazard for the mine based on the recent seismic history. An assessment of a mine-wide value for Mmax is performed based in the work presented by Kijko and Singh (2011) and Lasocki and Urban (2011). The spatial distribution of b-value and event density for the recent history is performed and used as input to a probabilistic evaluation of the spatial distribution of the seismic hazard. The results of this probabilistic calculation is presented in space in several ways through iso surfaces and pseudo volumetric rendering.

The probabilistic distribution of the peak-particle velocity is calculated for minodes and seismic hazard map in terms of the probabilistic evaluation of the strong ground motion being produced. The minodes can be interrogated and the contribution of different sources evaluated.

Further Reading:

Wesseloo, J 2018, ‘The Spatial Assessment of the Current Seismic Hazard State for Hard Rock Underground Mines’, Rock Mechanics and Rock Engineering.

Wesseloo, J. (2014) Evaluation of the spatial variation of the b-value, Journal of the Southern African Institute of Mining and Metallurgy, 114, October, pp. 823-828.

Wesseloo, J., Woodward, K. and Pereira, J. (2014) Grid-based analysis of seismic data, Journal of the Southern African Institute of Mining and Metallurgy, 114, October, pp. 815-822.

  • Isosurfaces of hazard rating

Seismic-production balance

Seismic-Production Balance

Principal Authors: Gerhard Morkel

Citation: Morkel I.G (2016). mXrap software app, Mining Induced Seismicity – Seismic-Production Balance app, version 1. Perth, Western Australia: The Australian Centre for Geomechanics, The University of Western Australia. https//:www.mXrap.com

Description: The Seismic-Production Balance app focuses on investigating the link between seismicity and production, specifically the balance between the two. Adjustment of certain seismic parameters enables the user to view the Energy Balance chart and view the influence of increasing production volume on the energy in the system. In addition to Potency charts, the app also includes some other parameters plotted as a function of production volume for further analysis. These parameters include: Cumulative Number of Events vs Production Volume, Displacement vs Production Volume and Potency vs Production Volume.

 

Rockburst damage potential

Rockburst damage potential

Principal Authors: Dan Cumming-Potvin  

Other Contributors: Johan Wesseloo, Paul Harris, Gerhard Morkel

Citation: Cumming-Potvin, D., Wesseloo, J. and Harris, P.C. (2015) mXrap software app, Mining Induced Seismicity – Rockburst Damage Potential, version 1. Perth, Western Australia: The Australian Centre for Geomechanics, The University of Western Australia. https//:www.mXrap.com

Description: This app is based on the Rockburst Damage Potential (RDP) system developed by Dan Heal (2010). This app provides an environment to edit the E1, E2, E3 and E4 components of RDP system as well as to display and interrogate these components, the Excavation Vulnerability Potential (EVP), the PPV factor and the RDP.

Further Reading: Heal, D., Hudyma, M. and Potvin, Y. (2006) Evaluating rockburst damage potential in underground mining. InGolden Rocks 2006, The 41st US Symposium on Rock Mechanics (USRMS) 2006 Jan 1. American Rock Mechanics Association.

  • Rockburst Damage Potential on surfaces

Large event analysis

Large Event analysis

Principal Authors: Wei Duan Other contributors: Johan Wesseloo, Paul Harris

Citation: Duan, W., Wesseloo, J. and Harris, P.C. (2015) mXrap software app, Mining Induced Seismicity – Large Event Analysis, version 1. Perth, Western Australia: The Australian Centre for Geomechanics, The University of Western Australia. https//:www.mXrap.com

Description: The large event analysis app provides the user with an easy and quick first assessment of the distribution of strong ground motion at excavations for a given event. Plots are given for a uniform and a double couple shear mechanism. Users can choose events from the database performing “what-if” analyses by overriding some or all the parameters. The app is limited to a linear distance analysis using a given strong ground motion relationship and does not take into account any wave-medium and wave-excavation interaction.

 

theoretical radiation pattern shown on excavation surfaces

Theoretical radiation pattern shown on excavation surfaces

Omori analysis tools

Omori analysis tools

Principal Authors: Kyle Woodward, Gerhard Morkel

Other contributors: Johan Wesseloo, Stuart Tierney

Citation: Woodward. K.R., Morkel G.I., Wesseloo, J. and Tiernery, S.T. (2017) mXrap software app, Mining Induced Seismicity – Omori Analysis Tools, version 1. Perth, Western Australia: The Australian Centre for Geomechanics, The University of Western Australia. https//:www.mXrap.com

Description: The Omori Analysis app provides several windows each dedicated to specific tasks. The window provides the ability to select a blast or blasts from the blast database for which the “Omori chart” is provided for the events within a specified volume around the blast(s) and a specified time after the blast(s). If more than one blasts is selected the individual and the stacked cumulative event distribution is provided.

Another window is dedicated to performing a best-fit of the Modified Omori Law to the events associated with a selected blast. The chosen volume and time window and the parameters for the MOL is saved. Another window dedicated to the analysis of these results is provided. The statistical and spatial distributions of the MOL parameters are assessed based on the saved parameters from the MOL best-fit.

The spatial and statistical distributions of the MOL parameters provide input to the re-entry analysis which is provided in another window. The re-entry assessment is based on the work by Vallejo’s and McKinnon (2010) and can be used in real time assessment of re-entry or for the back analysis of historical data to develop re-entry protocols.

Vallejos, J.A. and McKinnon, S.D. (2010) Temporal evolution of aftershock sequences for re-entry protocol development in seismically active mines. In: Van Sint, J.M. and Potvin, Y. (eds). 5th International Seminar on Deep and High Stress Mining, 2010 Santiago, Chile. Australian Centre for Geomechanics, pp. 199-214.

Further Reading: Vallejos, J.A. and McKinnon, S.D. (2010) Temporal evolution of aftershock sequences for re-entry protocol development in seismically active mines. In: Van Sint, J.M. and Potvin, Y. (eds). 5th International Seminar on Deep and High Stress Mining, 2010 Santiago, Chile. Australian Centre for Geomechanics, pp. 199-214.

Morkel, IG & Rossi-Rivera, P 2017, ‘The implementation and quantification of the Vallejos and McKinnon re-entry methodology’, in, Proceedings of the Eighth International Conference on Deep and High Stress Mining, 2017, Australian Centre for Geomechanics. https://papers.acg.uwa.edu.au/p/1704_58_Morkel/

Tierney, S & Morkel, IG 2017, ‘The optimisation and comparison of re-entry assessment methodologies for use in seismically active mines’, in, Proceedings of the Eighth International Conference on Deep and High Stress Mining, 2017, Australian Centre for Geomechanics. https://papers.acg.uwa.edu.au/p/1704_59_Tierney/

 

  • Three selected blasts with associated space-time filtered data

Seismic event quality

Seismic event quality

Principal Authors: Gerhard Morkel, Johan Wesseloo

Other Contributors: Paul Harris

Citation: Morkel, G.I., Wesseloo J. (2015) mXrap software app, Mining Induced Seismicity – Seismic Event Quality, version 1. Perth, Western Australia: The Australian Centre for Geomechanics, The University of Western Australia. https//:www.mXrap.com

Description: The seismic event quality app provides tools to evaluate the quality of the database and highlight potential bad quality data. Noise, blasts and bad quality data can be tagged and excluded from analysis in other apps. The event quality app includes potential blast detection, spatial filters and outlier detection.

Further Reading: Morkel, IG & Wesseloo, J 2017, ‘A technique to determine systematic shifts in microseismic databases’, in, Proceedings of the Eighth International Conference on Deep and High Stress Mining, 2017, Australian Centre for Geomechanics. https://papers.acg.uwa.edu.au/p/1704_17_Morkel/

Morkel, IG & Wesseloo, J 2017, ‘The effect of sensor frequency range on the estimation of the current hazard state’, in J.A. Vallejos (ed.), 9th International Symposium on Rockbursts and Seismicity in Mines, 15-17 November 2017 2017, Santiago, Chile.

Morkel, IG, Wesseloo, J & Harris, PC 2015, ‘Highlighting and quantifying seismic data quality concerns’, in PM Dight (ed.), Ninth International Symposium on Field Measurements in Geomechanics, 9-11 September 2015, Sydney, New South Wales, Australia, Australian Centre for Geomechanics, pp. 215-222.

 

System design

System design

Principal Authors: Johan Wesseloo

Other contributors: Kyle Woodward, Wei Duan, Paul Harris

Citation: Wesseloo, J., Woodward, K.R., Duan, W. and Harris, P.C. (2015) mXrap software app, Mining Induced Seismicity – System Design, version 1. Perth, Western Australia: The Australian Centre for Geomechanics, The University of Western Australia. https//:www.mXrap.com

Description: The seismic system design app provides tools to assess the system sensitivity in 3D space. The app uses the seismic database and sensor file for a chosen stable period to derive the Dx-mmin relationship. Where Dx is the distance to the Xth sensor, typically X = 5 mmin is the system sensitivity. This relationship is then used to plot the system sensitivity in 3D space for a given array of seismic sensors. A general indication of the location quality for different magnitudes is also provided based on given sensor arrays. The effect of losing or adding sensors in the array can be evaluated interactively.

Although further development was done since the publication of the following paper, it still provides a summary of the concepts used in this app: Wesseloo, J. (2011) Empirical methods for assessment of seismic system sensitivity, Transactions of the Institutions of Mining and Metallurgy: Section A, Mining Technology, vol. 120 (2), pp. 105–111.

 

  • Magnitude-Distance relationship obtained from data

Basic seismic monitoring

Basic seismic monitoring

 

Status: Alpha

Principal Author: Stuart Tierney

Contributing Authors: Paul Harris, Dan Cumming-Potvin

Citation: Tierney, S.R. (2017) mXrap software app, Basic Seismic Monitoring. Perth, Western Australia: The Australian Centre for Geomechanics, The University of Western Australia. https://www.mXrap.com

Description: The use of the Basic Seismic Monitoring application is intended for mine control room operators to monitor the latest seismicity and communicate event alerts and exclusion areas depending on site specific rules. Each site can setup their own event alert and exclusion settings in the Basic Seismic Monitoring (Admin) application and then the main application is a simplified interface for the viewer. Key features include:

  • Automatic events updating (no need to keep pressing “Reload Data”!).
  • Popup event alert notifications (to alert user when window is hidden/minimised).
  • Popup system alert notifications (triggered from threshold time without new events).
  • Plot exclusion areas and isolate single mine areas (e.g. single level plans).
  • Automatic View – quick zoom/rotate to the exclusion areas on screen.
  • Distance measurement – get the distance from any survey point to the nearest event alert.