1887

Abstract

Summary

Though the anisotropy exists popularly in the earth, it is frequently neglected both in geophysical data interpretation and in modelling. However, negligence of the electrical anisotropy can have a serious influence on near-surface prospecting, like airborne electromagnetic (AEM), especially in areas where the underground bears well-developed stratification. In this paper, we first put forward a modelling algorithm, named spectral element method (SEM), for airborne EM modelling for a three-axis anisotropic earth. SEM is a technique based on weighted residual method. The latter uses a polynomial basis function for SEM, which can achieve a high accuracy when increasing the polynomial order. We take as example a horizontal coplanar coil (HCP) of an AEM system to check the accuracy of our algorithm for anisotropic models and we compare the 3rd and 4th order SEM modelling results with 1-D semi-analytical solution for a half-space or layered-earth model. To study the anisotropic effect on AEM responses, we calculate and compare the responses for both isotropic and anisotropic abnormal bodies using 3rd to 5th order SEM. Finally, we analyse the influence of the order of SEM interpolation functions on the AEM responses.

Loading

Article metrics loading...

/content/papers/10.3997/2214-4609.201700500
2017-06-12
2024-03-29
Loading full text...

Full text loading...

References

  1. LeeJ H, XiaoT and LiuQ H
    , [2006] A 3-D spectral-element method using mixed-order curl conforming vector basis functions for electromagnetic fields. IEEE Transactions on Microwave Theory & Techniques, 54(1): 437–444.
    [Google Scholar]
  2. LiuYH, YinCC
    , [2014] 3D anisotropic modeling for airborne EM systems using finite-difference method. Journal of Applied Geophysics, 109: 186–194.
    [Google Scholar]
  3. HuangX, YinC, LiuY
    , et al. [2016] Application of spectral element method for airborne EM modeling. SEG Technical Program Expanded Abstracts2016, pp. 2248–2252.
    [Google Scholar]
http://instance.metastore.ingenta.com/content/papers/10.3997/2214-4609.201700500
Loading
/content/papers/10.3997/2214-4609.201700500
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error