Pure and Applied Geophysics

, Volume 171, Issue 9, pp 2407–2415 | Cite as

Effect of Loop Geometry on TEM Response Over Layered Earth

  • Youzheng Qi
  • Ling Huang
  • Xin Wu
  • Guangyou Fang
  • Gang Yu


A large horizontal loop located on the ground or carried by an aircraft are the most common sources of the transient electromagnetic method. Although topographical factors or airplane outlines make the loop of arbitrary shape, magnetic sources are generally represented as a magnetic dipole or a circular loop, which may bring about significant errors in the calculated response. In this paper, we present a method for calculating the response of a loop of arbitrary shape (for which the description can be obtained by different methods, including GPS localization) in air or on the surface of a stratified earth. The principle of reciprocity is firstly used to exchange the functions of the transmitting loop and the dipole receiver, then the response of a vertical or a horizontal magnetic dipole is calculated beforehand, and finally the line integral of the second kind is employed to get the transient response. Analytical analysis and comparisons depict that our work got very good results in many situations. Synthetic and field examples are given in the end to show the effect of loop geometry and how our method improves the precision of the EM response.


Transient electromagnetic method Principle of reciprocity Irregular loop source Stratified medium 



This work was supported by Chinese Government SinoProbe Plan (No. SinoProbe-09-02), and also by R&D of Key Instruments and Technologies for Deep Resources Prospecting (No. ZDYZ 2012-1-03). The authors would also like to thank the anonymous reviewers and the editor for useful suggestions that improved this study.


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Copyright information

© Springer Basel 2014

Authors and Affiliations

  • Youzheng Qi
    • 1
    • 2
  • Ling Huang
    • 1
  • Xin Wu
    • 1
  • Guangyou Fang
    • 1
  • Gang Yu
    • 3
  1. 1.Key Laboratory of Electromagnetic Radiation and Sensing TechnologyChinese Academy of SciencesBeijingChina
  2. 2.University of Chinese Academy of SciencesBeijingChina
  3. 3.BGP Inc.China National Petroleum CorporationZhuozhouChina

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