High-Accuracy Positioning For Geophysical Target Characterization

Geophysical technologies for supporting ordnance and explosive waste remediation have focused on the problems of detecting, locating, and mapping the presence of underground objects. Experience has shown that the majority of underground objects detected by these systems presents no safety hazard and do not need to be excavated. Researchers have shown a likelihood of being able to characterize buried targets via sophisticated imaging and inversion algorithms that require high-accuracy positioning systems coupled with high-fidelity geophysical sensor technologies. ENSCO has developed and demonstrated an integrated, self-contained, local-area, high-precision inertial navigation technology that provides sub-centimeter positioning accuracy over areas of a couple of square meters. The technology has been integrated with a Geonics EM-61HH and also demonstrated with a Geometrics G-858. Positioning accuracy has been verified using an independent method. In addition to 3-D position, the velocity and attitude of the sensor are also provided. The prospect of effective target characterization should be realizable with this addition of improved position data.