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.
References
Allard M (2007) On the Origin of the HTEM Species. In: Milkereit B (ed) Proceedings of exploration 07: fifth decennial international conference on mineral exploration, pp 355–374
Archie GE (1942) The electrical resistivity log as an aid in determining some reservoir characteristics. Trans AIME 146:54–62
Auken E, Christiansen AV, Jacobsen L, Sørensen KI (2008) A resolution study of buried valleys using laterally constrained inversion of TEM data. J Appl Geophys 65(1):10–20
Auken E, Christiansen AV, Westergaard JA, Kirkegaard C, Foged N, Viezzoli A (2009) An integrated processing scheme for high-resolution airborne electromagnetic surveys, the SkyTEM system. Explor Geophys 40:184–192
Bajc AF, Newton MJ (2007) Mapping the subsurface of waterloo region, Ontario, Canada; an improved framework of quaternary geology for hydrogeological applications. J Maps 2007:219–230. doi:10.4113/jom.2007.56
Beamish D (2002) The canopy effect in airborne EM. Geophysics 67(6):1720–1728. doi:10.1190/1.1527073
Berg CB, Mathers SJ, Kessler H, Keefer DA (2011) Synopsis of Current Three-dimensional Geological Mapping and Modeling in Geological Survey Organizations, vol 578. Circular, Illinois State Geological Survey, Illinois
Bosch JHA, Bakker MAJ, Gunnink JL, Paap BF (2009) Airborne electromagnetic measurements as basis for a 3D geological model of an Elsterian incision. Zeitschrift der Deutschen Gesellschaft für Geowissenschaften 160(3):249–258. doi:10.1127/1860-1804/2009/0160-0258
Brodie R, Sambridge M (2006) A holistic approach to inversion of frequency-domain airborne EM data. Geophysics 71(6):G301–G312
Carle SF, Fogg GE (1996) Transition probability-based indicator geostatistics. Math Geol 28(4):453–476. doi:10.1007/bf02083656
Christiansen AV, Auken E (2012) A global measure for depth of investigation. Geophysics 77(4):WB171–WB177
Christiansen AV, Auken E, Viezzoli A (2011) Quantification of modeling errors in airborne TEM caused by inaccurate system description. Geophysics 76(1):F43–F52. doi:10.1190/1.3511354
Constable SC, Parker RL, Constable CG (1987) Occam’s inversion: a practical algorithm for generating smooth models from electromagnetic sounding data. Geophysics 52(3):289–300
Daly C, Caers J (2010) Multi-point geostatistics—an introductory overview. First Break 28(9):39–47. doi:10.3997/1365-2397.2010020
Deutsch CV, Journel AG (1998) GSLIB: geostatistical software library and user’s guide, 2nd edn. Oxford University Press, Oxford
Geoscene3D (2013) (http://www.geoscene3d.com) November 6th http://www.geoscene3d.com. Accessed April 15th 2013
Goldman M, Tabarovsky L, Rabinovich M (1994) On the influence of 3-D structures in the interpretation of transient electromagnetic sounding data. Geophysics 59(6):889–901
Guillemoteau J, Sailhac P, Behaegel M (2012) Fast approximate 2D inversion of airborne TEM data: Born approximation and empirical approach. Geophysics 77(4):89–97. doi:10.1190/geo2011-0372.1
Gunnink JL, Bosch JHA, Siemon B, Roth B, Auken E (2012) Combining ground-based and airborne EM through artificial neural networks for modelling glacial till under saline groundwater conditions. Hydrol Earth Syst Sci 16:3061–3074
Jørgensen F, Sandersen PBE (2009) Buried valley mapping in Denmark: evaluating mapping method constraints and the importance of data density. Zeitschrift der Deutschen Gesellschaft für Geowissenschaften 160(3):211–223. doi:10.1127/1860-1804/2009/0160-0211
Jørgensen F, Sandersen P, Auken E (2003) Imaging buried quaternary valleys using the transient electromagnetic method. J Appl Geophys 53(4):199–213
Jørgensen F, Sandersen PBE, Auken E, Lykke-Andersen H, Sørensen K (2005) Contributions to the geological mapping of Mors, Denmark—A study based on a large-scale TEM survey. Bull Geol Soc Den 52:53–75
Jørgensen F, Møller RR, Sandersen PBE, Nebel L (2010) 3-D geological modelling of the Egebjerg area, Denmark, based on hydrogeophysical data. Geol Surv Den Greenl Bull 20:27–30
Jørgensen F, Scheer W, Thomsen S, Sonnenborg TO, Hinsby K, Wiederhold H, Schamper C, Burschil T, Roth B, Kirsch R, Auken E (2012) Transboundary geophysical mapping of geological elements and salinity distribution critical for the assessment of future sea water intrusion in response to sea level rise. Hydrol Earth Syst Sci 16(7):1845–1862. doi:10.5194/hess-16-1845-2012
Kessler H, Mathers S, Sobisch HG (2009) The capture and dissemination of integrated 3D geospatial knowledge at the British Geological Survey using GSI3D software and methodology. Comput Geosci 35(6):1311–1321. doi:10.1016/j.cageo.2008.04.005
Meagher D (1980) Octree encoding: a new technique for the representation, manipulation and display of arbitrary 3-D objects by computer. Technical report IPL-TR-80-111. Renssel Polytechnic Institute
Newman GA, Hohmann GW, Anderson WL (1986) Transient electromagnetic response of a three-dimensional body in a layered earth. Geophysics 51(8):1608–1627
Oldenborger GA, Pugin A, Pullan SE (2013) Airborne time-domain electromagnetics, electrical resistivity and seismic reflection for regional three-dimensional mapping and characterization of the Spiritwood Valley Aquifer, Manitoba Canada. Near Surf Geophys 11(1):63–74. doi:10.3997/1873-0604.2012023
Pryet A, Ramm J, Chiles JP, Auken E, Deffontaines B, Violette S (2011) 3D resistivity gridding of large AEM datasets: a step toward enhanced geological interpretation. J Appl Geophys 75:277–283. doi:10.1016/j.jappgeo.2011.07.006
Raiber M, White PA, Daughney CJ, Tschritter C, Davidson P, Bainbridge SE (2012) Three-dimensional geological modelling and multivariate statistical analysis of water chemistry data to analyse and visualise aquifer structure and groundwater composition in the Wairau Plain, Marlborough District, New Zealand. J Hydrol 436:13–34. doi:10.1016/j.jhydrol.2012.01.045
Ross M, Parent M, Lefebvre R (2005) 3D geologic framework models for regional hydrogeology and land-use management: a case study from a Quaternary basin of southwestern Quebec Canada. Hydrogeol J 13(5–6):690–707. doi:10.1007/s10040-004-0365-x
Royse KR (2010) Combining numerical and cognitive 3D modelling approaches in order to determine the structure of the Chalk in the London Basin. Comput Geosci 36(4):500–511. doi:10.1016/j.cageo.2009.10.001
Sandersen PBE (2008) Uncertainty assessment of geological models - a qualitative approach. In: Refsgaard JC, Kovar K, Haarder E, Nygaard E (eds) 2008. Credibility of Modelling. IAHS Publication, Calibration and Reliability in Groundwater modelling, pp 337–344
Sandersen PBE, Jørgensen F, Larsen NK, Westergaard JH, Auken E (2009) Rapid tunnel-valley formation beneath the receding Late Weichselian ice sheet in Vendsyssel Denmark. Boreas 38(4):834–851. doi:10.1111/j.1502-3885.2009.00105.x
Scharling PB, Rasmussen ES, Sonnenborg TO, Engesgaard P, Hinsby K (2009) Three-dimensional regional-scale hydrostratigraphic modeling based on sequence stratigraphic methods: a case study of the Miocene succession in Denmark. Hydrogeol J 17(8):1913–1933. doi:10.1007/s10040-009-0475-6
Sharpe DR, Hinton MJ, Russell HAJ, Desbarats AJ (2002) The need for basin analysis in regional hydrogeological studies: oak Ridges Moraine Southern Ontario. Geosci Can 29(1):3–20
Sharpe DR, Pugin A, Pullan SE, Gorrell G (2003) Application of seismic stratigraphy and sedimentology to regional hydrogeological investigations: an example from Oak Ridges Moraine, southern Ontario Canada. Can Geotech J 40(4):711–730. doi:10.1139/t03-020
Sharpe D, Russell HAJ, Logan C (2007) A regional 3-dimensional geological model of the Oak Ridges Moraine area, Ontario, Canada. J Maps 2007:239–253. doi:10.4113/jom.2007.58
Siemon B, Christiansen AV, Auken E (2009) A review of helicopter-borne electromagnetic methods for groundwater exploration. Near Surf Geophys 7(5–6):629–646
Sørensen KI, Auken E (2004) SkyTEM—A new high-resolution helicopter transient electromagnetic system. Explor Geophys 35:191–199
Sørensen KI, Effersø F, Auken E (2001) A hydrogeophysical Investigation of the Island of Drejø. Europ J Environ Eng Geophys 6:109–124
Stafleu J, Maljers D, Gunnink JL, Menkovic A, Busschers FS (2011) 3D modelling of the shallow subsurface of Zeeland, the Netherlands. Neth J Geosci-Geologie En Mijnbouw 90(4):293–310
Strebelle S (2002) Conditional simulation of complex geological structures using multiple-point statistics. Math Geol 34(1):1–21. doi:10.1023/a:1014009426274
Troldborg L, Refsgaard J, Jensen K, Engesgaard P (2007) The importance of alternative conceptual models for simulation of concentrations in multi-aquifer system. Hydrogeol J 15:843–860
Troldborg L, Jensen K, Engesgaard P, Refsgaard J, Hinsby K (2008) Using environmental tracers in modeling flow in a complex shallow aquifer system. J Hydrol Eng 12(11):1037–1048
Turner AK (2006) Challenges and trends for geological modelling and visualisation. Bull Eng Geol Environ 65(2):109–127. doi:10.1007/s10064-005-0015-0
Venteris ER (2007) Three-dimensional modeling of glacial sediments using public water-well data records: an integration of interpretive and geostatistical approaches. Geosphere 3(6):456–468. doi:10.1130/ges00090.1
Viezzoli A, Christiansen AV, Auken E, Sørensen KI (2008) Quasi-3D modeling of airborne TEM data by spatially constrained inversion. Geophysics 73(3):F105–F113
Viezzoli A, Jørgensen F, Sørensen C (2013) Flawed processing of airborne EM data affecting hydrogeological interpretation. Ground Water. doi:10.1111/j.1745-6584.2012.00958.x
West GF, Macnae JC (1991) Physics of the electromagnetic induction exploration method. In: Nabighian MN, Corbett JD (eds) Electromagnetic methods in applied geophysics, vol 2. Investigations in geophysics, Society of exploration geophysicists, pp 5–45
Wycisk P, Hubert T, Gossel W, Neumann C (2009) High-resolution 3D spatial modelling of complex geological structures for an environmental risk assessment of abundant mining and industrial megasites. Comput Geosci 35(1):165–182. doi:10.1016/j.cageo.2007.09.001
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.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Jørgensen, F., Møller, R.R., Nebel, L. et al. A method for cognitive 3D geological voxel modelling of AEM data. Bull Eng Geol Environ 72, 421–432 (2013). https://doi.org/10.1007/s10064-013-0487-2
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10064-013-0487-2