Mining Publication: Apparent Earth Conductivity Over Coal Mines as Estimated from Through-the-Earth Electromagnetic Transmission Tests
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Original creation date: January 1984
Electromagnetic narrow-band signals were transmitted through the earth at 27 coal mines located throughout the United States. From those Bureau of Mines tests, apparent earth conductivity values were derived based upon a homogeneous half-space model of the earth. The derived conductivity values were found to be inversely proportional to the transmitted frequency and mine depth. A linear regression model relating the logarithm of the conductivity to the mine depth was formulated, and the results indicate that the mine depth can be an adequate predictor of the apparent earth conductivity above coal mines. Apparent earth conductivity was found to decrease with mine depths.
Authors: JA Durkin
Report of Investigations - January 1984
NIOSHTIC2 Number: 10003475
Source Pittsburgh, PA: U.S. Department of the Interior, Bureau of Mines,NTIS PB84-213792, RI 8869, 1984 Jan; :1-18
See Also
- Adaptive-Noise-Cancellation Techniques for Through-the-Earth Electromagnetics: Volume III
- Preliminary Performance Predictions For Electromagnetic Through-The-Earth Mine Communications: A Collection of Working Memoranda
- Propagation of EM Signals in Underground Mines
- Research and Development Contract for Coal Mine Communication System: Volume 3 - Theoretical Data Base
- Theoretical Noise and Propagation Models for Through-the-earth Communication
- Through-the-earth Electromagnetic Trapped Miner Location Systems. A Review
- Through-The-Earth Wireless Real-Time Two-Way Voice Communications
- Two-Way, Through-the-Earth Emergency Communication System for Trapped Miners and the Surface
- Ultra-Low Frequency Through-the-Earth Communication Technology
- Vertical Magnetic Noise in the Voice Frequency Band Within and Above Coal Mines
- Content source: National Institute for Occupational Safety and Health, Mining Program