EM61-MK2 Response of Three Munitions Surrogates
Abstract
Target response coefficients for three pipe nipples intended as surrogates for commonly encountered UXO items were calculated from measurements made using the recently developed NRL Time-domain Electromagnetic Induction array. These response coefficients were used to predict the signals expected from an EM61-MK2, the most commonly used geophysical survey instrument for UXO, for each of the three items as a function of orientation and distance of the center of the item below the bottom coil of the sensor. A series of EM61-MK2 survey measurements were made over the surrogates at the NRL Blossom Point Test site to confirm the predictions. The predicted EM61-MK2 signals are presented graphically as plots of the minimum signal expected at the second time gate as a function of distance from the sensor with the confirming survey measurements plotted on the same axes. The minimum signal at each of the four gates available from the EM61-MK2 is tabulated for depths corresponding to 3x, 5x, 7x and 11x the object's diameter and all the results obtained are attached electronically as a spreadsheet.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 12, 2009
- Accession Number
- ADA495842
Entities
People
- D. A. Steinhurst
- Herbert H. Nelson
- J. Kingdon
- N. Khadr
- T. Bell
Organizations
- United States Naval Research Laboratory