Rapid Screening of Large-area Magnetic Data for Unexploded Ordnance
L.P. Beard*, D.A. Wolf, T.J. Gamey, W.E. Doll, Oak Ridge National Laboratory, Oak Ridge, Tennessee, U.S.A.;
B. Spurgeon, Geosoft Europe Ltd., Wallington, Oxfordshire, UK
Paper – [pdf] UXO_SAGEEP_RapidScreening_for_uxo_LPB_2003
Airborne magnetic surveys can cover hundreds of hectares with very close sensor spacing in a single day. Over UXO-contaminated areas this can translate to thousands of anomalies. Any tool that permits one to rapidly classify anomalies as probable non-UXO and probable UXO is useful. Several geophysical characteristics can be exploited to sort the anomalies, among them signal ampli-tudes, estimated source depth, and indicators
of magnetic remanence. We have developed a grid-based technique that combines information from the total field residual anomaly, the analytic signal, and sensor height to estimate source depth and remanent magnetization. We can then use these and other indicators in statistical schemes to predict whether the source of an anomaly is or is not ordnance.