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A method for cognitive 3D geological voxel modelling of AEM data

  • Flemming Jørgensen
  • Rasmus Rønde Møller
  • Lars Nebel
  • Niels-Peter Jensen
  • Anders Vest Christiansen
  • Peter B. E. Sandersen
Original Article

Abstract

Airborne electromagnetic (AEM) data have proven successful for the purpose of near-surface geological mapping and are increasingly being collected worldwide. However, conversion of data from measured resistivity to lithology is not a straightforward task. Therefore, it is still challenging to make full use of these data. Many limitations must be considered before a successful geological interpretation can be performed and a reasonable 3D geological model constructed. In this paper, we propose a method for 3D geological modelling of AEM data in which the limitations are jointly considered together with a cognitive and knowledge-driven data interpretation. The modelling is performed iteratively by using voxel modelling techniques with tools developed for this exact purpose. Based on 3D resistivity grids, the tools allow the geologist to select voxel groups that define any desirable volumetric shape in the 3D model. Recent developments in octree modelling ensure exact modelling with a limited number of voxels.

Keywords

Three-dimensional geological model Airborne electromagnetic data Voxel modelling Octree Groundwater 

Notes

Acknowledgments

The software development is a part of the HYACINTS research project funded by The Danish Council for Strategic Research, Danish Agency for Science Technology and Innovation. Jens Christian Refsgaard is thanked for his helpful comments on an early version of the paper. Two anonymous reviewers are thanked for their reviews and helpful comments.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Flemming Jørgensen
    • 1
  • Rasmus Rønde Møller
    • 1
  • Lars Nebel
    • 2
  • Niels-Peter Jensen
    • 2
  • Anders Vest Christiansen
    • 3
  • Peter B. E. Sandersen
    • 1
  1. 1.Geological Survey of Denmark and Greenland, GEUSHøjbjergDenmark
  2. 2.I-GIS A/SRisskovDenmark
  3. 3.Department of GeoscienceAarhus UniversityAarhus CDenmark

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