1887
2nd Australasian Exploration Geoscience Conference: Data to Discovery
  • ISSN: 2202-0586
  • E-ISSN:

Abstract

Summary

Conductivity depth data presentations derived using 1D approximations have become a very popular way to present airborne electromagnetic (AEM) data. While data profiles and a single error limit per station can accompany these presentations there are more information contained in data. This work proposes some ideas for augmenting 1D derived data presentations to highlight two and three-dimensional conductors as well as more detailed error level indication. The 1D conductivity depth algorithm used is an extended version of the S-layer differential transform. The depths calculated with the transform is used also present decay constant values corrected for conductive background responses. Fraser filtered X-component data are used to indicate structural complexity and data fit error levels are used to grey out areas on the depth section presentations where the results are less reliable. To demonstrate these ideas a line of Xcite data over the Abra deposit in Western Australia is analysed. The augmentations add valuable information to the conductivity depth section in the sense of drawing attention the where the 1D assumptions are not valid and should encourage interpreters to pursue 2D or 3D modelling techniques for successfully mapping the ore deposit.

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/content/journals/10.1080/22020586.2019.12072981
2019-12-01
2026-01-13
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References

  1. Combrinck, M., 2008, Calculation of conductivity and depth correction factors for the S-layer differential transform: Exploration Geophysics, 39, 133–138.
  2. Combrinck, M., and Botha, W. J., 2011, Decay characteristics of airborne time-domain electromagnetic data-Where to find the constant (tau): 12th Biennial Conference and Exhibition, SAGA, Cape Town, Oral presentation
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  6. Tartaras, E., Zhdanov, M. S., Wada, K., Saito, A., and Hara, T., 2000, Fast imaging of TDEM data based on S-inversion: Journal of Applied Geophysics, 43, 15–32
  7. Ward, S. H. and Hohmann, G. W.: 1988, Electromagnetic Methods in Applied Geophysics, Vol. 1, Theory, Society of Exploration Geophysicists, Chapt.4, pp 131-250
/content/journals/10.1080/22020586.2019.12072981
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  • Article Type: Research Article
Keyword(s): Abra; CDI; decay constant; inversion; Xcite
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