MINING MINING MINING MINING MINING 
Project Fact Sheet 
24-CHANNEL GEOPHONE ARRAY FOR HORIZONTAL 
BENEFITS 
OR VERTICAL BOREHOLES 
• Saves energy by minimizing 
mining interruptions 
• Decreases the amount of waste 
that is mined 
• Improves mining productivity 
APPLICATION 
Development of a 24-channel 
geophone array will benefit surface 
and underground metal, industrial, 
and coal mines by increasing the 
accuracy of tomographic imaging 
through source and receiver 
locations that completely surround 
the area of interest. 
24-CHANNEL GEOPHONE ARRAY ELIMINATES PROBLEM OF 
SENSOR PLACEMENT 
This project will develop an array of 24 seismic sensors capable of being mounted 
in either a vertical or horizontal borehole. Seismic tomography has been used 
successfully to monitor and evaluate geologic conditions ahead of a mining face. 
A primary limitation of existing seismic tomography, however, is the placement of 
sensors. This 24-channel geophone array may eliminate this problem of sensor 
placement. It will significantly increase the accuracy of tomographic imaging of 
conditions ahead of mining by allowing source and receiver locations to completely 
surround the area of interest. This technology will save energy in excavation, 
transportation, ventilation, and processing phases of mining operations. It will also 
reduce the amount of waste mined and mining cycle interruptions. 
Three primary components are critical to the design. First, conventional measuring 
devices are lowered into vertical holes, a reliable placement method is required for 
horizontal boreholes. Second a unit which houses the geophone and allows 
clamping to the borehole wall must be designed. Finally, the geophone must be 
electronically connected to the data acquisition system with appropriate cable and 
connectors. The development of this array will minimize mining interruptions and 
improve productivity. 
SEISMIIC SENSORS 
Above illustration shows seismic sensors in dry a vertical borehole for 
surface mining/quarrying. 
OFFICE OF INDUSTRIAL TECHNOLOGIES 
ENERGY EFFICIENCY AND RENEWABLE ENERGY U.S. DEPARTMENT OF ENERGY
Project Description 
Goal: To develop an array of 24 seismic sensors capable of being mounted in 
either vertical or horizontal boreholes to improve ground-imaging techniques. This 
will reduce energy usage in mining operations because anomalous conditions 
ahead of mining will be more clearly imaged, allowing fewer interruptions and less 
waste material mined. 
The primary research tasks will focus on sensor placement method, sensor 
housing and clamping, and cabling and connector selection. Following assembly, 
a prototype will be tested in the laboratory as well as in both an underground coal 
mine and a surface stone quarry. Data analysis and tool performance will then be 
used for subsequent design modifications. A final design will have several 
components available for patent application. 
Progress and Milestones 
This project includes the following activities: 
• Finalize design and assemble arrays including sensors, housing and clamping 
units as well as cabling and connect issues. 
• Laboratory testing will focus on the clamping and placement components. 
• Apply for Mining Safety and Health Administration (MSHA) Experimental Permit 
to allow it to be used in a methane drainage borehole of an underground mine. 
• Field tests at surface quarry and underground coal mine. 
• Data analysis of the clamping repeatability, placement ease, and sensor 
response will be evaluated during laboratory and field testing. 
• Alter array design based on test results. 
• Prepare final report. 
Commercialization Plan 
Project support from companies which are actively involved in borehole equipment 
and ground imaging will assure that the developed technology is transferred to 
industry. Further, two publications will describe the ability, usage, and advantages 
of the technology. These publications will be in highly visible forums so that 
numerous additional representatives of the mining industry will be aware of the 
development of the technology. 
PROJECT PARTNERS 
Virginia Polytechnic Institute 
and State University 
Blacksburg, VA 
CONSOL Inc. 
Library, PA 
Global Stone James River 
Buchanan, VA 
NSA Engineering, Inc. 
Golden, CO 
FOR ADDITIONAL INFORMATION, 
PLEASE CONTACT: 
Office of Industrial Technologies 
Clearinghouse 
Phone: (800) 862-2086 
Fax: (360) 586-8303 
clearinghouse@ee.doe.gov 
Visit our home page at 
www.oit.doe.gov/mining 
Office of Industrial Technologies 
Energy Efficiency 
and Renewable Energy 
U.S. Department of Energy 
Washington, D.C. 20585 
January 2001