USING CROSS-BOREHOLE ELECTROMAGNETIC PROBING TO LOCATE A TUNNEL

Theoretical and experimental studies of electromagnetic interaction with a tunnel found that signal minima can be used to detect and locate the tunnel. These minima are found on the transmission side of the tunnel, the side opposite the signal transmitter. From the appearance of the signal and comparison with Fresnel diffraction, the main mechanism of signal interaction with the tunnel seems to be diffraction rather than refraction or reflection. Experiments were made around a tunnel near Gold Hill, Colorado. The tunnel was horizontally and vertically located within three feet. (ERA citation 02:033061)

• Corporate Authors:

  University of California, Livermore

  Lawrence Livermore National Laboratory
  Livermore, CA  United States  94550

  Department of Energy

  1000 Independence Avenue, SW
  Washington, DC  United States  20585
• Authors:
  • Lytle, R J
  • Lager, D L
  • Laine, E F
  • Davis, D T
• Publication Date: 1976-10-21

Media Info

• Features: References;
• Pagination: 45 p.

Subject/Index Terms

• TRT Terms: Boreholes; Coefficients; Diffraction; Electromagnetic pulses; Electromagnetic radiation; Location; Radar; Surveys; Tunnels
• Old TRIS Terms: Diffraction methods; Fresnel coefficient; Topological mapping
• Subject Areas: Bridges and other structures; Railroads;

Filing Info

• Accession Number: 00167258
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: DOT/TST-77-76
• Contract Numbers: W-7405-ENG-48
• Files: TRIS
• Created Date: Nov 23 1978 12:00AM