1887
6th International Conference in Airborne Electromagnetics (AEM 2013)
  • ISSN: 0812-3985
  • E-ISSN: 1834-7533

Abstract

[

Spectral 3D approximations of the EM response can efficiently model vortex induction and current gathering for simple geological target geometries. This paper presents results of a spectral model fitting algorithm to automatically pick, locate and define a sulphide target from VTEM data at the Forrestania test range, Western Australia

,

Virtually all airborne electromagnetic (AEM) data is interpreted using stitched 1D conductivity sections, derived from constrained inversion or fast but fairly accurate approximations. A small subset of this AEM data recently has been inverted using either block 3D models or thin plates, which processes have limitations in terms of cost and accuracy, and the results are in general strongly biased by the choice of starting models. Recent developments in spectral modelling have allowed fast 3D approximations of the EM response of both vortex induction and current gathering for simple geological target geometries. Fitting these spectral responses to AEM data should be sufficient to accurately locate current systems within the ground, and the behaviour of these local current systems can in theory approximately define a conductivity structure in 3D. This paper describes the results of initial testing of the algorithm in fitting vortex induction in a small target at the Forrestania test range, Western Australia, using results from a versatile time-domain electromagnetic (VTEM)-Max survey.

]
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2015-03-01
2026-01-16

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/content/journals/10.1071/EG14036
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3D-spectral CDIs: a fast alternative to 3D inversion?
Exploration Geophysics 46, 12 (2015); https://doi.org/10.1071/EG14036
/content/journals/10.1071/EG14036
/content/journals/10.1071/EG14036
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  • Article Type: Research Article
Keyword(s): 3D conductivity-depth imaging; airborne; electromagnetics; spectral inversion

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