Altitude correction of time domain AEM data for image display and geological mapping using the Apparent Dipole Depth (ADD) method

Abstract

This paper describes a procedure called the Apparent Dipole Depth (ADD) method for simple correction of airborne TEM data for the effects of changing aircraft altitude. The method uses the receding image concept of Maxwell and assumes that the earth is horizontally layered. It is necessary that the data can be converted to step response (B field at the sensor for a step-off in current). In spite of the limitations inherent in these assumptions, careful application of the method results in a great improvement in the interpretability of images of the early time channels.