HR: 13:50h
AN: GP23A-02 INVITED     [Abstracts]
TI: Advances in High-Resolution Magnetometry for Mapping Unexploded Ordnance (UXO) and the Challenge of Geologic Noise
AU: * Nyquist, J E
EM: nyq@temple.edu
AF: Department of Geology Temple University, 1901 N 13th Street, Philadelphia, PA 19122 United States
AU: Boufadel, M C
EM: boufadel@temple.edu
AF: Department of Civil & Environmental Engineering, 1947 North 12th Street, Philadelphia, PA 19122 United States
AU: Doll, W E
EM: d8e@ornl.gov
AF: Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 United States
AB: We discuss recent advances in the application of high-resolution magnetometry to UXO site characterization, focusing specifically on large-area assessment using helicopter-based magnetic surveys with flight lines only a few meters apart at heights of 1-2 meters above ground level. Motivating this work is the estimated cost of UXO clean-up: roughly 50 billion dollars for military bases in the U.S., involving some 1400 sites and over 10 million acres of land. Excavation is the principal remediation cost because setting detection thresholds low enough to minimize the risk of overlooking UXO generates numerous false positives, each of which must be treated as potentially explosive. The current U.S. Defense Department goal is to reduce the false-positive ratio from 100:1 down to 10:1 using improved geophysical sensors systems coupled with sophisticated discrimination algorithms. Discrimination involves not just sorting the bombs from the scrap metal, but also identification of UXO in the presence of geologic noise. Geologic noise at UXO sites can range from minimal (Badlands Bombing Range, South Dakota) to severe (Pueblo of Isleta bombing targets, New Mexico) and can change dramatically at a given site as a function of the survey scale. We discuss research to characterize geologic noise scaling using a multifractal approach with the eventual goal of simulating the affect of geologic noise on UXO discrimination algorithms.
DE: 0910 Data processing
DE: 0925 Magnetic and electrical methods
DE: 0994 Instruments and techniques
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2005 Joint Assembly