Share Email Print

Proceedings Paper

Integrated geophysical approach to the detection of buried objects and clandestine tunnels
Author(s): James W. Allen
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

A planned and integrated geophysical approach, using all available data, has proven effective in detecting shallow tunnels and buried objects in different geological environments. Elements of the integrated approach included information from intelligence, historical reviews, computer modelling, and multiple geophysical survey methods. The use of the integrated approach resulted in a higher rate of success in detecting tunnels and small objects at shallow depths; however, no single survey technique has been universally effective. Several different survey methods were used to determine specific characteristics of a potential target. Magnetic sensors detected ferromagnetic materials used in tunnel construction. Analyses of the magnetic anomaly characteristics and the surface patterns of the anomalies indicated the depth and path of the tunnel. Tunnels were also detected by intrinsic parameters of observed electromagnetic anomalies and the surface patterns of instrument responses. Both methods have successfully differentiated materials used in tunnel construction and operational support systems from surface features such as utility or sewer lines. Cross-borehole radar was used to confirm the existence of a deep tunnel through crystalline rock in the southern part of the Demilitarized Zone in the Republic of Korea. Additional indications of tunnels were obtained from analyses of migrated seismic compression waves (P-waves) collected by a vertical stack, common- midpoint method. Ground-penetrating radar (GPR) and magnetic and EM sensors were effective in detecting shallow-depth caches constructed of various materials.

Paper Details

Date Published: 28 August 1992
PDF: 9 pages
Proc. SPIE 1693, Surveillance Technologies II, (28 August 1992); doi: 10.1117/12.138104
Show Author Affiliations
James W. Allen, U.S. Dept. of Energy and Chem-Nuclear Geotech, Inc. (United States)

Published in SPIE Proceedings Vol. 1693:
Surveillance Technologies II
Sankaran Gowrinathan; James F. Shanley, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?