Accession Number:

ADA505829

Title:

Utilizing Seismic/Acoustic Sensors to Protect Secure Facilities from Underground Intrusion

Descriptive Note:

Conference paper

Corporate Author:

ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS

Personal Author(s):

• McKenna, Jason R.
• Kelley, Julie R.
• Berry, Thomas E.
• Rowan, James R.
• Wakeley, Lillian D.
• Tucker, Robert E.

Report Date:

2008-12-01

Pagination or Media Count:

8.0

Abstract:

A seismicacoustic array was developed to detect activity in clandestine tunnels. The geologic setting of the area that encloses clandestine tunneling activity can preclude use of traditional tunnel-detection technologies such as ground-penetrating radar GPR. Properties of the sediments at the study site are attributable to original environment of deposition and subsequent natural and human-caused modifications. The resulting lateral and vertical variability in critical soil properties confounded GPR and electromagnetic techniques, but did not appear to have a negative impact on propagation of seismicacoustic signals from digging and movement within a test tunnel. The team developed algorithms that distinguish the signals from digging and human movement from those of surface activity. Prolonged rainfall at the tunnel site caused an increase in signal amplitude, and allowed the team to quantify the signal changes from the full range of mechanical and Soldier noise on a Forward Operating Base FOB. Understanding the impacts of variability in soil density, moisture content, and grain size may allow further refinement of the algorithm.

Descriptors:

• *ACOUSTIC ARRAYS
• *TUNNELING
• *SEDIMENTS
• *SEISMIC DETECTION
• SAND
• SOIL MECHANICS
• ACOUSTIC SIGNALS
• GEOPHYSICS
• DESERTS
• SEISMIC SIGNATURES
• SOIL TESTS
• GRAIN SIZE
• OFF THE SHELF EQUIPMENT
• GEOPHONES
• ALGORITHMS
• SYMPOSIA

Subject Categories:

• Hydrology, Limnology and Potamology
• Acoustic Detection and Detectors
• Seismic Detection and Detectors

Distribution Statement:

APPROVED FOR PUBLIC RELEASE