Technical Papers - Airborne Electromagnetics

Approximate Apparent Conductance (or Conductivity) from the Realisable Moments of the Impulse Response

Richard S. Smith, Peter Annan, Fugro Airborne Surveys, 2060 Walkley Rd., Ottawa, ON, Canada, K1G 3P5
Terry J. Lee, P.O. Box 1984, Canberra, ACT 2601, Australia
M.D. O'Connell (Consultant), 1679 Laurelwood Pl., Orleans, Ontario, Canada, K1C 6Y4

Introduction

The moments of the impulse response can be used for converting the electromagnetic response to an apparent conductance or conductivity of the ground. By taking into account the finite off time and the periodic nature of the EM response, higher-order moments can be used to estimate the properties of the ground. In effect this allows estimates to be obtained from late-time data, and this will reflect the more conductive bodies, or the deeper parts (when the geology is quasi layered). Moment images show some asymmetry artifacts (“herringboning”), but not as strong as the herringbones on time-constant images.

Published in Geophysics, January-February, 2005, volume 70, pages G29-G32. © 2005 Society of Exploration Geophysicists. All rights reserved.

Download Paper (PDF 217 Kb)