Shape-based classification and discrimination of subsurface objects using electromagnetic induction

Abstract

We consider discrimination between differently-shaped subsurface objects using electromagnetic induction sensors. For compact objects sufficiently far from the sensor, the response can be represented in terms of an induced dipole moment which is related to the primary field by a frequency-dependent magnetic polarizability tensor. This response tensor depends on the size, shape and material properties of the target. We present results of recent work on how the properties of the response depend on the target shape and on how conventional electromagnetic induction sensors can be used for subsurface discrimination.