Airborne Transient EM Methods and Their Applications for Coastal Groundwater Investigations

  • C. Schamper
  • J. B. Pedersen
  • E. Auken
  • A. V. Christiansen
  • B. Vittecoq
  • J. Deparis
  • T. Jaouen
  • F. Lacquement
  • P. Nehlig
  • J. Perrin
  • P.-A. Reninger
Chapter
Part of the Coastal Research Library book series (COASTALRL, volume 7)

Abstract

For more than half a century airborne electromagnetic (AEM) methods have been used worldwide for cost-effective resistivity mapping of areas larger than several hundred km2. The technical developments and intensive use of these systems, principally in mining exploration during the first decades, led to the development of helicopter transient EM (HTEM) systems. Since the 2000s these systems provide the best lateral and vertical resolution for environmental exploration, and they still keep a good depth of investigation allowing the exploration from the first meters to depths of several hundred meters. This chapter focuses on helicopter borne transient electromagnetic (HTEM) systems, which are well suited for the detection of low resistive targets such as salt water intrusion in coastal zones.

AEM methods are based on the diffusive induction phenomenon. It is a key tool for building realistic hydrogeological models; however it requires an understanding of its limits, and some insight into data processing modeling is necessary. They require careful processing, and removal of cultural EM noise, present in most survey areas, is mandatory in order to get high quality results. Accurate modeling of the data and of the system is also critical. The modeling is most often based on least-square optimization algorithms giving smooth or layered model descriptions of ground.

In this chapter we describe the AEM method in detail and we discuss processing and inversion of data. To demonstrate the results from an investigation, we end the chapter with a case study of a SkyTEM survey made in the volcanic island of Mayotte where key geological structures and salt water intrusion were successfully mapped.

Keywords

Seawater Intrusion Saline Aquifer Secondary Field Ground Resistivity High Resistive Layer 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgement

This work was carried out with the financial support of the Mayotte Prefecture and Department, the French Ministry of Environment, SIEAM (local water supply authority) and BRGM, the French geological survey.

References

  1. Albouy Y, Andrieux P, Rakotondrasoa G, Ritz M, Descloitres M, Join J-L, Rasolomanana E (2001) Mapping coastal aquifers by joint inversion of DC and TEM soundings – three case histories. Ground Water 39(1):87–97CrossRefGoogle Scholar
  2. Allard M (2007) On the origin of the HTEM species. In: Proceedings of exploration: fifth decennial international conference on mineral exploration, Toronto, 2007, pp 355–374Google Scholar
  3. Audru JC, Guennoc P, Thinon I, Abellard O (2006) Bathymay: la structure sous-marine de Mayotte révélée par l’imagerie multifaisceaux. CR Geosci 338(16):1240–1249CrossRefGoogle Scholar
  4. Auken E, Christiansen AV (2004) Layered and laterally constrained 2D inversion of resistivity data. Geophysics 69(3):752–761CrossRefGoogle Scholar
  5. Auken E, Christiansen AV, Westergaard JA, Kirkegaard C, Foged N, Viezzoli A (2009a) An integrated processing scheme for high-resolution airborne electromagnetic surveys, the SkyTEM system. Explor Geophys 40(2):184–192CrossRefGoogle Scholar
  6. Auken E, Violette S, d’Ozouville N, Deffontaines B, Sorensen KI, Viezzoli A, de Marsily G (2009b) An integrated study of the hydrogeology of volcanic islands using helicopter borne transient electromagnetic: application in the Galapagos Archipelago. CR Geosci 34(10–11):899–907CrossRefGoogle Scholar
  7. Auken E, Foged N, Roth B, Mikkelsen P (2010a) SkyTEM survey Mayotte 2010, Survey report, Department of Geoscience, Aarhus UniversityGoogle Scholar
  8. Auken E, Foged N, Sørensen KI (2010b) Approaching 10 microsec (and earlier) with the SkyTEM system. In: ASEG extended abstract, 21st international geophysical conference and exhibition, Sydney, 22–26 Aug 2010Google Scholar
  9. Auken E, Mikucki J, Sørensen KI, Schamper C, Sab G-A, Tulaczyk S (2012) First airborne transient EM survey in Antarctica: mapping of saline ground water system. In: Remote sensing-near surface geoscience extended abstract, 18th European meeting of environmental and engineering geophysics, Paris, 3–5 Sept 2012Google Scholar
  10. Blaschek R, Hördt A, Kemna A (2008) A new sensitivity-controlled focusing regularization scheme for the inversion of induced polarization data based on the minimum gradient support. Geophysics 73(2):F45–F54CrossRefGoogle Scholar
  11. Buselli G, Williamson DR (1996) Modeling of broadband airborne electromagnetic responses from saline environments. Geophysics 61(6):1624–1632CrossRefGoogle Scholar
  12. Christiansen AV, Auken E (2012) A global measure for depth of investigation. Geophysics 77(4):171–177Google Scholar
  13. Christiansen AV, Auken E, Sørensen KI (2006) The transient electromagnetic method. In: Kirsch R (ed) Groundwater geophysics: a tool for hydrogeology. Springer, BerlinGoogle Scholar
  14. Christiansen AV, Auken E, Viezzoli A (2011) Quantification of modeling errors in airborne TEM caused by inaccurate system description. Geophysics 76(1):F43–F52CrossRefGoogle Scholar
  15. Cox LH, Wilson GA, Zhdanov MS (2012) 3D inversion of airborne electromagnetic data. Geophysics 77(4):WB59–WB69CrossRefGoogle Scholar
  16. Cruz JV, Silva MO (2001) Hydrogeologic framework of Pico Island, Azores, Portugal. Hydrogeol J 9(2):177–189CrossRefGoogle Scholar
  17. Cruz JV, Coutinho R, Pacheco D, Cymbron R, Antunes P, Freire P, Mendes S (2011) Groundwater salinization in the Azores archipelago (Portugal). Environ Earth Sci 62(6):1273–1285CrossRefGoogle Scholar
  18. Custodio E (2004) Hydrogeology of volcanic rocks. In: Kovalevsky VS, Kruseman GP, Rushton GR (eds) Groundwater studies: an international guide for hydrogeological investigations. UNESCO, Paris, pp 395–425Google Scholar
  19. Custodio E, Lopez GL, Amigo E (1988) Simulation par modèle mathématique de l’île volcanique de Ténériffe (Canaries, Espagne). Hydrogéologie 2:153–167Google Scholar
  20. Debeuf D (2004) Etude de l’évolution volcano-structurale et magmatique de Mayotte (Archipel des Comores, Océan Indien), approche structurale, pétrographique géochimique et géochronologique). PhD thesis of The University of La Réunion, 277 pGoogle Scholar
  21. d’Ozouville N, Auken E, Sorensen KI, Violette S, de Marsily G (2008) Extensive perched aquifer and structural implications revealed by 3D resistivity mapping in a Galapagos volcano. Earth Planet Sci Lett 269(3–4):517–521Google Scholar
  22. Descloitres M, Ritz M, Robineau B, Courteaud M (1997) Electrical structure beneath the eastern collapsed flank of Piton de la Fournaise volcano, Reunion Island: implications for the quest of groundwater. Water Resour Res 33(1):13–19CrossRefGoogle Scholar
  23. Emerick CM, Duncan RA (1982) Age progressive volcanism in the ComoroArchipelago, western IndianOcean and implications for Somali plate tectonics. Earth Planet Sci Lett 60(3):415–428CrossRefGoogle Scholar
  24. Farquharson CG, Oldenburg DW (1993) Inversion of time-domain electromagnetic data for a horizontally layered Earth. Geophys J Int 114(3):433–442CrossRefGoogle Scholar
  25. Fitterman DV, Deszcz-Pan M (1998) Helicopter EM mapping of saltwater intrusion in Everglades National Park, Florida. Explor Geophys 29(2):240–243CrossRefGoogle Scholar
  26. Fitterman DV, Meekes JAC, Ritsema IL (1988) Equivalence behavior of three electrical sounding methods as applied to hydrogeological problems. In: EAGE, 50th annual meeting, The Hague, 1988Google Scholar
  27. Foged N, Auken E, Christiansen AV, Sørensen KI (2013) Test site calibration and validation of airborne and ground based TEM-systems. Geophysics 78(2):E95–E106Google Scholar
  28. Fountain D (1998) Airborne electromagnetic systems – 50 years of development. Explor Geophys 29(2):1–11CrossRefGoogle Scholar
  29. Fountain D (2008) 60 years of airborne EM – focus on the last decade. In: Proceedings of the 5th international conference on airborne electromagnetics (AEM2008), Haikko Manor, 28–30 May 2008Google Scholar
  30. Gubbins D (2004) Time series analysis and inverse theory for geophysicists. Cambridge University Press, Cambridge/New York, 272 ppCrossRefGoogle Scholar
  31. Henderson A (2007) ParaView guide, a parallel visualization application. Kitware Inc., Clifton ParkGoogle Scholar
  32. Herrera C, Custodio E (2008) Conceptual hydrogeological model of volcanic Easter Island (Chile) after chemical and isotopic surveys. Hydrogeol J 16(7):1329–1348CrossRefGoogle Scholar
  33. Izuka SK, Gingerich SB (2003) A thick lens of fresh groundwater in the southern Lihue Basin, Kauai, Hawaii, USA. Hydrogeol J 11(2):240–248CrossRefGoogle Scholar
  34. 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):1845–1862CrossRefGoogle Scholar
  35. Kim Y, Lee K-S, Koh D-C, Lee D-H, Lee S-G, Park W-B, Koh G-W, Woo N-C (2003) Hydrogeochemical and isotopic evidence of groundwater salinization in a coastal aquifer: a case study in Jeju volcanic island, Korea. J Hydrol 270(3–4):282–294CrossRefGoogle Scholar
  36. Kirkegaard C, Sonnenborg TO, Auken E, Jørgensen F (2011) Salinity distribution in heterogeneous coastal aquifers mapped by airborne electromagnetics. Vadose Zone J 10(1):125–135CrossRefGoogle Scholar
  37. Lénat JF, Fitterman D, Jackson DB, Labazuy P (2000) Geoelectrical structure of the central zone of Piton de la Fournaise volcano (Réunion). Bull Volcanol 62(2):75–89CrossRefGoogle Scholar
  38. Lienert BR (1991) An electromagnetic study of Maui’s last active volcano. Geophysics 56(7):972–982CrossRefGoogle Scholar
  39. Macnae JC, Lamontagne Y, West GF (1984) Noise processing techniques for time-domain EM systems. Geophysics 49(7):934–948CrossRefGoogle Scholar
  40. Marquardt DW (1963) An algorithm for least-squares estimation of nonlinear parameters. J Soc Ind Appl Math Control 11(2):431–441CrossRefGoogle Scholar
  41. Marquardt DW (1970) Generalized inverses, ridge regression, biased linear estimation and nonlinear estimation. J Soc Ind Appl Math Control 12(3):591–612Google Scholar
  42. Menke W (1989) Geophysical data analysis: discrete inversion theory. Academic, San Diego, 260 ppGoogle Scholar
  43. Møller I, Verner H, Søndergaard VH, Flemming J, Auken E, Christiansen AV (2009) Integrated management and utilization of hydrogeophysical data on a national scale. Near Surf Geophys 7(5–6):647–659Google Scholar
  44. Munkholm MS, Auken E (1996) Electromagnetic noise contamination on transient electromagnetic soundings in culturally disturbed environments. J Environ Eng Geophys 1(2):119–127CrossRefGoogle Scholar
  45. Nougier J, Cantagrel JM, Karche JP (1986) The Comores archipelago in the western Indian Ocean: volcanology, geochronology and geodynamic setting. Journal of African Earth Sciences (1983) 5(2):135–144Google Scholar
  46. Paine JG (2003) Determining salinization extent, identifying salinity sources, and estimating chloride mass using surface, borehole, and airborne electromagnetic induction methods. Water Resour Res 39(3):3-1–3-10CrossRefGoogle Scholar
  47. Peterson FL (1972) Water development on tropic volcanic islands. Type example: Hawaii. Ground Water 10(5):18–23CrossRefGoogle Scholar
  48. Portniaguine O, Zhdanov MS (2002) 3-D magnetic inversion with data compression and image focusing. Geophysics 67(5):1532–1541CrossRefGoogle Scholar
  49. Pryet A, d’Ozouville N, Violette S, Deffontaines B, Auken E (2012) Hydrogeological settings of a volcanic island (San Cristóbal, Galapagos) from joint interpretation of airborne electromagnetics and geomorphological observations. Hydrol Earth Syst Sci Discuss 9(8):9661–9686CrossRefGoogle Scholar
  50. Sab G-A (2012) Data processing of an Airborne Electromagnetic survey in Antarctica. Master thesis made at the Hydrogeogphysics Group, Aarhus University, AarhusGoogle Scholar
  51. Schamper C, Auken E, Sørensen KI (2012) A new processing system for very early time SkyTEM101 data. In: ASEG, 22nd international geophysical conference and exhibition, Brisbane, 26–29 Feb 2012Google Scholar
  52. Siemon B, Christiansen AV, Auken E (2009) A review of helicopter-borne electromagnetic methods for groundwater exploration. Near Surf Geophys 7(5–6):629–646Google Scholar
  53. Sørensen KI, Auken E (2004) SkyTEM – a new high-resolution helicopter transient electromagnetic system. Explor Geophys 35(3):191–199Google Scholar
  54. Stieltjes L (1988) Hydrogéologie de l’île volcanique océanique de Mayotte (Archipel des Comores, ocean indien occidental). Hydrogéologie 2:135–151Google Scholar
  55. Teatini P, Tosi L, Viezzoli A, Baradello L, Zecchin M, Silvestri S (2011) Understanding the hydrogeology of the Venice Lagoon subsurface with airborne electromagnetics. J Hydrol 411(3–4):342–354CrossRefGoogle Scholar
  56. Thomsen R, Søndergaard VH, Sørensen KI (2004) Hydrogeological mapping as a basis for establishing site-specific groundwater protection zones in Denmark. Hydrogeology 12(5):550–562CrossRefGoogle Scholar
  57. Tikhonov AN, Arsenin VY (1977) Solution of ill-posed problems. V.H. Winston and Sons, Washington, DC, 258 ppGoogle Scholar
  58. Viezzoli A, Christiansen AV, Auken E, Sørensen KI (2008) Quasi-3D modeling of airborne TEM data by spatially constrained inversion. Geophysics 73(3):F105–F113CrossRefGoogle Scholar
  59. Vittecoq B, Deparis J, Auken E, Nehlig P, Perrin J, Puvilland P, Martelet G (2011a) Buried valleys revealed by helicopter borne transient electromagnetic and hydrogeological implications: example of the volcanic island of Mayotte. In: 2011 GSA annual meeting, Minneapolis, 9–12 Oct 2011Google Scholar
  60. Vittecoq B, Jaouen T, Deparis J (2011b) Programme de recherche et d’exploitation des eaux souterraines de Mayotte – 5ème campagne de forage à Mayotte. Révision des implantations. REPORT/RP-60035-FR, BRGM, Orléans, FranceGoogle Scholar
  61. Ward SH, Hohmann GW (1988) Electromagnetic theory for geophysical applications. In: Nabighian MN (ed) Electromagnetic methods in applied geophysics, vol 1. SEG, Tulsa, pp 131–311Google Scholar
  62. Werner AD, Bakkerd M, Posta VEA, Vandenbohede A, Lua C, Ataie-Ashtiania B, Simmonsa CT, Barrye DA (2012) Seawater intrusion processes, investigation and management: recent advances and future challenges. Adv Water Resour 51, 24 ppGoogle Scholar
  63. Witherly K, Irvine R, Morrison E (2004) The Geotech VTEM time domain helicopter EM system. In: ASEG extended abstracts, 17th international geophysical conference and exhibition, Sydney, 15–19 Aug 2004Google Scholar
  64. Yang D, Oldenburg DW (2012) Three-dimensional inversion of airborne time-domain electromagnetic data with applications to a porphyry deposit. Geophysics 77(2):B23–B34CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  • C. Schamper
    • 1
  • J. B. Pedersen
    • 1
  • E. Auken
    • 1
  • A. V. Christiansen
    • 1
  • B. Vittecoq
    • 2
  • J. Deparis
    • 3
  • T. Jaouen
    • 4
  • F. Lacquement
    • 3
  • P. Nehlig
    • 3
  • J. Perrin
    • 3
  • P.-A. Reninger
    • 3
  1. 1.HydroGeophysics Group (HGG), Department of GeoscienceAarhus UniversityAarhusDenmark
  2. 2.Basse Normandie Geological SurveyBRGMHérouville-Saint-ClairFrance
  3. 3.Georesources DivisionBRGMOrléansFrance
  4. 4.Mayotte Geological SurveyBRGMMamoudzouFrance

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