ASA 130th Meeting - St. Louis, MO - 1995 Nov 27 .. Dec 01

5aPAa12. The detection of objects buried in sand using airborne sound-induced seismic vibrations.

James M. Sabatier

Tom M. Troutman

Natl. Ctr. for Phys. Acoust., Univ. of Mississippi, University, MS 38677

Objects buried in air-saturated sand can be detected by measuring the normal component of matrix velocity or acceleration in the vicinity of the object. A loudspeaker positioned 1.15 m away and 1.15 m above the surface is driven in the frequency range between 1 and 4.2 kHz. Geophones, accelerometers, and an off-the-shelf laser Doppler vibrometer are used to measure the normal velocity component. Surface images of the object are formed by making many point velocity or acceleration measurements with a geophone or accelerometer. An LDV will also be used to produce noncontact, scanned images of small targets in sand. The resolution of this technique is discussed. Also, water-saturated sand will be investigated.