Mining Publication: Local Earthquake Tomography for Imaging Mining-Induced Changes Within the Overburden above a Longwall Mine
Original creation date: July 2008
Three-dimensional velocity tomograms were generated on a daily basis to image mining-induced changes to the overburden above a longwall mine. The hypothesis was that a coherent redistribution of seismic velocity, due to the development of high-stress zones, could be imaged at the mine scale. Seam depth was 360 m and source location depth varied from 100 to 1000 m. Sixteen geophones were distributed over a 600 by 600 m square area on the surface above the mine. More than 12,500 events were recorded over an 18 day period. The recorded seismicity provided input for the local-earthquake tomography code, SIMULPS. Eighteen tomograms were generated and high-velocity regions correlated well with high abutment stresses. Additionally, the high-velocity regions were observed to redistribute as the longwall face retreated. These results indicate that velocity tomography can be used to provide a better understanding of temporal changes within a rock mass, and can potentially be used to produce a better understanding of the mechanisms that lead to unanticipated ground failures.
Authors: EC Westman, KD Luxbacher, PL Swanson
Conference Paper - July 2008
NIOSHTIC2 Number: 20034343
42nd U.S. Rock Mechanics Symposium/2nd U.S.-Canada Rock Mechanics Symposium, June 29 - July 2, 2008, San Francisco, California, ARMA 08-299. The American Rock Mechanics Association, 2008; :1-7
See Also
- Coal Mine Safety Applications of Seismic Monitoring
- Degasification System Selection for U.S. Longwall Mines Using an Expert Classification System
- Detecting Strata Fracturing and Roof Failures from a Borehole Based Microseismic System
- Development of Stress Measurements and Instrument Placement Techniques for Longwall Coal
- Ground Control Research: Considering Local Geology to Improve Longwall Pillar Stability
- Improvements in Seismic Event Locations in a Deep Western U.S. Coal Mine Using Tomographic Velocity Models and an Evolutionary Search Algorithm
- Large-Scale Strata Response to Longwall Mining: A Case Study
- Microseismic Activity Associated With a Deep Longwall Coal Mine
- Seismic Monitoring Strategies for Deep Longwall Coal Mines
- Time-Lapse Tomography of a Longwall Panel: A Comparison of Location Schemes
- Page last reviewed: 9/21/2012
- Page last updated: 9/21/2012
- Content source: National Institute for Occupational Safety and Health, Mining Program