Industrial Mining and Explosions

Industrial Explosions as Seismic Sources
Geophysical Imaging Archive
Geosciences Web Archive

David P. Anderson, SMU
Brian W. Stump, SMU, LANL
D. Craig Pearson, LANL
Xiaoning Yang, LANL


Physical Constraints on Mining Explosions
Synergy of Seismic and Video Data with Three Dimensional Models

This is the HTML Web page version of a paper prepared for Seismological Research Letters, Spring 1996. It includes gif and jpeg images as well as mpeg movies of mining blasts and synthetic computer models.


The following MPEG movies document the SMU/Los Alamos mine blasting experiments in 1995 and 1996 as described in the report titled "Reducing the Ambiguity and Visibility of Seismic Signals from Mining Activities."

16 June 1995
This mpeg movie taken from within the pit of the coal mine is of a large cast blast. Video of the explosion has been deinterlaced and time tagged.


16 June 1995 Waveforms
Observed ground motions and a model of the blast (turns from white to red at design shot time) have been superimposed and time correlated with the video images of the explosion.


16 June 1995 Model
A model depicting the generation and propagation of the compressional energy resulting from the detonation of each of the individual borehole in the 16 June explosion. The design shot times of the explosion were used to create the visualization.


13 November 1995
This mpeg movie taken from within the pit of the coal mine is of a large cast blast. Video of the explosion has been deinterlaced and time tagged.


13 November 1995 Waveforms
Observed ground motions and acoustic wavewforms and a model of the blast (turns from white to red at design shot time) have been superimposed and time correlated with the video images of the explosion. Note the large peak amplitude at late time in the ground motions which is reflective of the simultaneous detonation of several boreholes towards the end of the shot.


13 November 1995 Model
A model depicting the generation and propagation of the compressional energy resulting from the detonation of each of the individual borehole in the 13 Nov explosion. The simultaneous detonation of several boreholes at the end of the shot is depicted.


11 March 1995
This mpeg movie taken from the bench at the end of the pit is of a large cast blast. Video of the explosion has been deinterlaced and time tagged.


11 March 1995 Spoils
This mpeg movie taken from the spoils pile overlooking the pit is of a large cast blast. Video of the explosion has been deinterlaced and time tagged.


01 August 1996
This mpeg movie taken from the spoils pile overlooking the pit is of a large cast blast. Video of the explosion has been deinterlaced and time tagged.


Primary and Auxiliary Seismic Stations
This mpeg movie represents the Primary and Auxiliary seismic stations proposed as part of the International Monitoring System for the Comprehensive Test Ban Treaty. As the globe turns the model zooms into a mine in NE Wyoming where video from a large explosion is played. Explosions such as this one may produce seismic signals that will be detected by some of the seismic stations in the International Monitoring System.





The Tyrnyauz Molybdenum Mine (59k jpeg) This is one of the largest moly mines in the world, operated continuously for over 50 years by the former Soviet Union in Tyrnyauz, in the Russian autonomous republic of Kabardino-Balkaria. In 1993 an international seismic research team led by Brian W. Stump of SMU were the first western scientists ever to instrument and document the blasting practices at the Tyrnyauz mine. The gif image is 248k.

The Tyrnyauz Blast (399k mpeg) These images document mining practices in a moly mine of the former Soviet Union in Tyrnyauz, in the Russian autonomous republic of Kabardino-Balkaria.. This blast used bore holes approximately 12 inches in diameter and 36 feet deep, loaded with ANFO explosive. The holes were not stemmed (backfilled) and thus produced huge airblasts. The gif image of the blast is 197k.

Tyrnyauz Blast Model (395k mpeg) This model simulates a 500 frames per second slow motion film of the Tyrnyauz moly mine blast, including the row-by-row delay times and the sequential firing of the explosive charges. The blue rings represent the seismic wavefronts moving out at about 3000 meters per second. The yellow rings represent the accompanying slower airblasts.




Multi-Shot Experiment (550k mpeg) American open-pit coal mine blasting. This experiment studied a small 4x4 array shot which was heavily instrumented both at close range and regional distances. Velocity gauges and accelerometers as well as velocity-of-detonation (VODR) recoders and hi-speed film and video cameras were used to form combined data sets used to quantify seismic source processes. This is not really a movie, just 6 stills in mpeg format.


Multi-Shot Blast (470k mpeg) Digitized video has been de-interlaced and de-jittered to produce half speed images of the blast. This is then combined with ground motion data collected from 3-axis accelerometers installed near the camera locations. Note the coupling (or lack) of the ripple fired charges as they go off in sequence. Note also how little seismic energy is generated from the re-impacting of the lofted material.


Multi-Shot Model (520k mpeg) The ground motions and detonation timing are combined in this computer model of the multiple shot sequence. Three axis ground motion waveforms are dislayed with a moving cursor for temporal reference. Timing delays deviate from those designed by the blaster as documented by down-hole VODR and hi-speed film analysis.



HYDROFRAC (2.19Meg mpeg) Seismic Verification of Hydraulic Fracture Geometry. This experiment was performed by the Shell Western Exploration and Production Bellaire Research Center in Houston, Texas. A single "treatment well" was surrounded by three "monitor wells" which gathered seismic signals during the course of the experiment. An hydraulic slurry was pumped under high pressure to produce a confined fracture at the base of the treatment well. Seismic data was then analyzed to determine the size and extent of the fracturing. This visualization models the timing and location of the seismic events and compares the predicted and actual fracture size, area, and orientation.




The following papers are in Adobe Acrobat format (".pdf" files) and require the Adobe Acrobat reader, which is freely available for a wide variety of computing platforms from www.adobe.com.

Source Moment Tensor Estimation of Surface Mining Blasts

This paper reports the results of a study which characterizes the single mining shot in terms of its source moment tensor representation. The study uses near-source, broad band ground motion data collected in a controlled field experiment composed of 8 single-hole surface mining shot sources. The results reveal characteristics of this particular kind of seismic source which are useful for understanding the physical source processes involved and improving our ability to discriminate. This 840k pdf document is a Los Alamos National Laboratory Technical Report, LA-UR-96-4684.


The White Pine Controlled Collapse Experiment

Underground collapses can generate seismic waves that in some instances are observed at regional (> 1000 km) distances. A physical understanding of these types of sources may allow them to be distinguished from other seismic sources such as earthquakes and explosions. This paper describes results from a near-source and regional seismic monitoring experiment conducted during an explosively triggered underground mine collapse. The analysis includes a characterization of the primary collapse as well as aftershocks that followed the event. This 5.3 megabyte pdf document is a Los Alamos National Laboratory Technical Report, LAUR-96-2642.


Quantification and Characterization of Regional Seismic Signals from Cast Blasting in Mines

Cast blasts in coal mines, designed to move large volumes of overburden, are a source of large (1-5 kt), frequent explosions in parts of the world with near-surface coal resources. Mining events of this source type are triggering the prototype International Monitoring System for the Comprehensive Test Ban Treaty being tested under the Group of Scientific Experts Technical Test 3 (GSETT-3). We wish to develop techniques to distinguish between the seismic signals produced by these explosions and equivalent size single (or point) sources. To that end, we have developed a linear elastic model to simulate regional-distance seismograms from mining cast blasts. This 8.2 megabyte pdf document is a Los Alamos National Laboratory Technical Report, LAUR-96-3747.


Azimuthal Variation of Radiation of Seismic Energy from Cast Blasts
D.Craig Pearson, Brian W. Stump, Los Alamos National Laboratory,
Robert L. Martin, Thunder Basin Coal Company.


Experimental Study of Seismic Energy Generated by Large Scale Mine Blasting
Robert L. Martin, David Gross, Thunder Basin Coal Company
D.Craig Pearson, Brian W. Stump, Los Alamos National Laboratory
David P. Anderson, Southern Methodist University


Regional Observations of Mining Blasts by the GSETT-3 Seismic Monitoring System
Brian W. Stump, D.Craig Pearson, Los Alamos National Laboratory



SMU Geological Sciences Archive

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Last modified: 14 Sept 2008
(c)1995-2008 David P. Anderson