Overview of multimethod geophysical system development for enhanced near-surface target detection, discrimination, and characterization

Abstract

Near-surface geophysical “targets” include unexploded ordnance (UXO), landmines, cavities (including tunnels and underground facilities), contaminant plumes, utilities (including underground storage tanks, pipelines, etc.), archaeological artifacts, graves, forensic evidence, structural foundation investigations for new and existing structures, and assessing the condition of engineered structures (e.g., bridges, dams, levees, roads, airfields, buildings). Application of near-surface geophysics to detect and characterize any of these “targets” is in the public interest, and many applications are clearly and directly related to public safety. While the detection of these targets in a geologic background can often be challenging, the discrimination of the desired target signatures or expressions from “false alarm” target signatures can be an even greater challenge. The discrimination challenge can be as simple as a “go/no-go” decision on the target, or the properties of the target may need to be further characterized after the decision. There is near unanimity among geophysicists (a rare thing) that multimethod, collocated complementary geophysical data enhance not only target detection but also the capability for discrimination and characterization. The U.S. Army Engineer Research and Development Center (ERDC) conducted a multiyear research and development effort that resulted in complementary, collocated simultaneous geophysical survey capabilities for near-surface targets.