1887
Volume 40, Issue 2
  • ISSN: 0812-3985
  • E-ISSN: 1834-7533

Abstract

We present an application of spatially constrained inversion (SCI) of SkyTEM (airborne electromagnetic) data for defining spatial patterns of salinisation in the Bookpurnong irrigation area located in the lower Murray Basin of South Australia. SCI uses Delaunay triangulation to set 3D constraints between neighbouring soundings, taking advantage of the spatial coherency that may be present in the dataset. Conductivity information for individual soundings is linked through the spatial constraints, from well determined parameters to locally poorly determined parameters. For the survey presented here, SCI generated maps detail the spatial variability of floodplain salinisation, the extent of floodplain sediments influenced by lateral recharge and flushing along stretches of the Murray River, and the variable quality of groundwater in deeper semi-confined aquifers of the Murray Group. Available borehole and other ancillary information, such as vegetation density and health patterns, match the observed conductivity variations seen in the SCI results, even at the very near surface (≈2m depth). The SCI provides more accurate and spatially consistent results compared with those from single site inversions. They are also more uniform and detailed than maps obtained with single point Layered Earth Inversions or a laterally constrained inversion. In this example, the SCI provided reliable quasi 3D modelling, that confirmed and improved the hydrogeological knowledge of the area, indicating that the technique would have application with helicopter electromagnetic data in similar settings throughout the lower Murray Basin of Australia.

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2009-06-01
2026-01-12
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References

  1. Auken E. Christiansen A. V. 2004Layered and laterally constrained 2D inversion of resistivity data: Geophysics 69 752 761 doi:10.1190/1.1759461
    [Google Scholar]
  2. Auken E. , Christiansen A. V. , Jacobsen L. , and Sørensen K. I. 2005, Laterally Constrained 1D-Inversion of 3D TEM Data SAGEEP 2005, Atlanta, USA, EEGS.
  3. Auken E. Jørgensen F. Sørensen K. I. 2003Large-scale TEM investigation for groundwater: Exploration Geophysics 34 188 194 doi:10.1071/EG03188
    [Google Scholar]
  4. Berens V. Hatch M. A. 2006In stream geophysics (NanoTEM): a tool to help identify salt accession risk: Australian Society of Exploration Geophysics Preview 120 20 25
    [Google Scholar]
  5. Berens V. , White M. G. , Souter N. J. , Jolly I. D. , Holland K. L. , McEwan K. L. , Hatch M. A. , Fitzpatrick A. D. , and Munday T. J. 2007, Surface Water, Groundwater and Ecological Interactions along the River Murray A Pilot Study of Management Initiatives at the Bookpurnong Floodplain, South Australia, Proceedings of the IAH meeting, 10 pp.
  6. Brown C. M. , and Stephenson A. E. 1991, Geology of the Murray Basin, Southeastern Australia: BMR Bulletin 235, 430 pp.
  7. Delaunay B. N. 1934, Sur la sphere vide: Izvestia Akademii Nauk SSSR, Otdelenie Matematicheskii i Estestvennyka Nauk (Bulletin of Academy of Sciences of the USSR) 7 793 800
    [Google Scholar]
  8. Huang H. Fraser D. C. 2003Inversion of helicopter electromagnetic data to a magnetic conductive layered earth: Geophysics 68 1211 1223 doi:10.1190/1.1598113
    [Google Scholar]
  9. Jolly I. D. , Holland K. L. , McEwan K. L. , Overton I. C. , White M. G. , Berens V. , and Mensforth L. J. 2006, The ‘Bookpurnong Experiment’: will groundwater management and flooding improve the health of the floodplain vegetation? Proceedings International Conference on ‘Hydro Eco 2006 – Hydrology and Ecology: The Groundwater/Ecology Connection’, Karlovy Vary, Czech Republic, 11–14 September, pp 305–308.
  10. Lane R. 2000, Conductive unit parameters: summarising complex conductivity distributions: 70th Meeting, SEG, Calgary, Expanded Abstracts, Volume 1, Section EM4.2, pp 328–331.
  11. Munday, T. J., Doble, R., Berens, V., and Fitzpatrick, A., 2005, The application of air, ground and ‘in river’ electromagnetics in the definition of spatial patterns of groundwater induced salt accumulation in a salinising floodplain, lower River Murray, South Australia, Proceedings of the 19th Annual SAGEEP Symposium, April 2–6, 2005. SAGEEP, Seattle, USA.
  12. Newman G. A. Anderson W. L. Hohmann G. W. 1987Interpretation of transient electromagnetic soundings over three-dimensional structures for the central-loop configuration: Geophysical Journal of the Royal Astronomical Society 89 889 914
    [Google Scholar]
  13. Overton, I., and Jolly I., 2004, Integrated Studies of Floodplain vegetation Health, saline groundwater and flooding on the Chowilla floodplain South Australia. CSIRO LW Tech Report 20/04, 169 pp.
  14. Sattel D. 1998Conductivity information in three dimensions: Exploration Geophysics 29 157 162 doi:10.1071/EG998157
    [Google Scholar]
  15. Sattel D. 2005Inverting airborne electromagnetic (AEM) data with Zohdy’s method: Geophysics 70 G77 G85 doi:10.1190/1.1990217
    [Google Scholar]
  16. Sengpiel K. P. Siemon B. 2000Advanced inversion methods for airborne electromagnetic exploration: Geophysics 65 1983 1992 doi:10.1190/1.1444882
    [Google Scholar]
  17. Sørensen K. I. Auken E. 2004SkyTEM – A new high-resolution helicopter transient electromagnetic system: Exploration Geophysics 35 191 199 doi:10.1071/EG04194
    [Google Scholar]
  18. Viezzoli A. Christiansen A. V. Auken E. Sørensen K. 2008Quasi-3D modeling of airborne TEM data by spatially constrained inversion: Geophysics 73 F105 F113 doi:10.1190/1.2895521
    [Google Scholar]
  19. White M. G. , Berens V. , Souter N. J. , Holland K. L. , McEwan K. L. , and Jolly I. D. 2006, Vegetation and groundwater interactions on the Bookpurnong floodplain, South Australia, Proceedings 10th Murray-Darling Basin Groundwater Workshop, Canberra 18th–20th September 2006.
  20. Wolfgram P. Karlik G. 1995Conductivity-depth transform of GEOTEM data: Exploration Geophysics 26 179 185 doi:10.1071/EG995179
    [Google Scholar]
  21. Yan W. , Howles S. , Howe B. , and Hill T. 2005, Loxton–Bookpurnong numerical groundwater model 2005 South Australian Government, Department of Water Land and Biodiversity Conservation Report 2005/17 Report prepared for the Murray Darling Basin Commission.
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