Articles | Volume 26, issue 11
https://doi.org/10.5194/hess-26-2813-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/hess-26-2813-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Technical note
| 
02 Jun 2022
Technical note |
| 02 Jun 2022
| 02 Jun 2022
Technical note: Efficient imaging of hydrological units below lakes and fjords with a floating, transient electromagnetic (FloaTEM) system
Pradip Kumar Maurya
CORRESPONDING AUTHOR
HydroGeophysics Group, Department of Geoscience, Aarhus University, Høegh-Guldbergs Gade 2, 8000 Aarhus C, Denmark
Frederik Ersted Christensen
HydroGeophysics Group, Department of Geoscience, Aarhus University, Høegh-Guldbergs Gade 2, 8000 Aarhus C, Denmark
Masson Andy Kass
HydroGeophysics Group, Department of Geoscience, Aarhus University, Høegh-Guldbergs Gade 2, 8000 Aarhus C, Denmark
Jesper B. Pedersen
HydroGeophysics Group, Department of Geoscience, Aarhus University, Høegh-Guldbergs Gade 2, 8000 Aarhus C, Denmark
Rasmus R. Frederiksen
HydroGeophysics Group, Department of Geoscience, Aarhus University, Høegh-Guldbergs Gade 2, 8000 Aarhus C, Denmark
Nikolaj Foged
HydroGeophysics Group, Department of Geoscience, Aarhus University, Høegh-Guldbergs Gade 2, 8000 Aarhus C, Denmark
Anders Vest Christiansen
HydroGeophysics Group, Department of Geoscience, Aarhus University, Høegh-Guldbergs Gade 2, 8000 Aarhus C, Denmark
Esben Auken
HydroGeophysics Group, Department of Geoscience, Aarhus University, Høegh-Guldbergs Gade 2, 8000 Aarhus C, Denmark
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Cited articles
Auken, E., Jørgensen, F., and Sørensen, K. I.: Large-scale TEM
investigation for groundwater, Explor. Geophys., 33, 188–194, 2003.
Auken, E., Christiansen, A. V., Westergaard, J. A., Kirkegaard, C., Foged,
N., and Viezzoli, A.: An integrated processing scheme for high-resolution
airborne electromagnetic surveys, the SkyTEM system, Explor. Geophys., 40, 184–192, 2009.
Auken, E., Christiansen, A. V., Fiandaca, G., Schamper, C., Behroozmand, A.
A., Binley, A., Nielsen, E., Effersø, F., Christensen, N. B., Sørensen, K. I., Foged, N., and Vignoli, G.: An overview of a highly versatile forward and stable inverse algorithm for airborne, ground-based and borehole electromagnetic and electric data, Explor. Geophys., 46, 223–235, 2015.
Auken, E., Foged, N., Larsen, J., Lassen, K., Maurya, P., Dath, S., and
Eiskjær, T.: tTEM – A towed transient electromagnetic system for detailed 3D imaging of the top 70 m of the subsurface, Geophysics, E13–E22,
https://doi.org/10.1190/geo2018-0355.1, 2018.
Binley, A. and Kemna, A.: DC Resistivity and Induced Polarization Methods,
in: Hydrogeophysics, edited by: Rubin, Y. and Hubbard, S. S., Springer
Netherlands, Dordrecht, 129–156, https://doi.org/10.1007/1-4020-3102-5_5, 2005.
Briggs, M. A., Nelson, N., Gardner, P., Solomon, D. K., Terry, N., and Lane,
J. W.: Wetland-Scale Mapping of Preferential Fresh Groundwater Discharge to
the Colorado River, Groundwater, 57, 737–748, https://doi.org/10.1111/gwat.12866, 2019.
Christiansen, A. V., Auken, E., and Sørensen, K. I.: The transient electromagnetic method, in: Groundwater Geophysics. A tool for hydrogeology,
1st Edn., edited by: Kirsch, R., Springer, 179–224, https://doi.org/10.1007/3-540-29387-6_6, 2006.
Christiansen Vest, A. and Auken, E.: A global measure for depth of investigation, Geophysics, 77, WB171–WB177, 2012.
Danielsen, J. E., Auken, E., Jørgensen, F., Søndergaard, V., and
Sørensen, K. I.: The application of the transient electromagnetic method in hydrogeophysical surveys, J. Appl. Geophys., 53, 181–198, 2003.
Day-Lewis, F. D., White, E. A., Johnson, C. D., Lane, J. W., and Belaval, M.: Continuous resistivity profiling to delineate submarine groundwater discharge – examples and limitations, Leading Edge, 25, 724–728, https://doi.org/10.1190/1.2210056, 2006.
Dickey, K. A.: Geophysical investigation of the Yellowstone Hydrothermal
System, Geophysics, Virginia Tech, 110 pp., 2018.
Fitterman, D. V. and Deszcz-Pan, M.: Helicopter EM mapping of saltwater
intrusion in Everglades National Park, Florida, Explor. Geophys., 29,
240–243, https://doi.org/10.1071/EG998240, 1998.
Gustafson, C., Key, K., and Evans, R. L.: Aquifer systems extending far offshore on the US Atlantic margin, Scient. Rep., 9, 1–10, 2019.
Harvey, J. and Gooseff, M.: River corridor science: Hydrologic exchange and
ecological consequences from bedforms to basins, Water Resour. Res., 51, 6893–6922, https://doi.org/10.1002/2015WR017617, 2015.
Hatch, M., Munday, T., and Heinson, G.: A comparative study of in-river
geophysical techniques to define variations in riverbed salt load and aid
managing river salinization, 75, WA135–WA147, https://doi.org/10.1190/1.3475706, 2010.
Hinsby, K., Markager, S., Kronvang, B., Windolf, J., Sonnenborg, T. O., and Thorling, L.: Threshold values and management options for nutrients in a catchment of a temperate estuary with poor ecological status, Hydrol. Earth Syst. Sci., 16, 2663–2683, https://doi.org/10.5194/hess-16-2663-2012, 2012.
Jørgensen, F., Møller, R. R., Sandersen, P. B., and Nebel, L.: 3-D geological modelling of the Egebjerg area, Denmark, based on hydrogeophysical data, GEUS Bull., 20, 27–30, 2010.
Kwon, H.-S., Kim, J.-H., Ahn, H.-Y., Yoon, J.-S., Kim, K.-S., Jung, C.-K., Lee, S.-B., and Uchida, T. J. E. G.: Delineation of a fault zone beneath a
riverbed by an electrical resistivity survey using a floating streamer cable, Explor. Geophys., 36, 50–58, 2005.
Lane, J. W., Briggs, M. A., Maurya, P. K., White, E. A., Pedersen, J. B.,
Auken, E., Terry, N., Minsley, B., Kress, W., LeBlanc, D. R., Adams, R., and
Johnson, C. D.: Characterizing the diverse hydrogeology underlying rivers and estuaries using new floating transient electromagnetic methodology, Sci. Total Environ., 740, 140074, https://doi.org/10.1016/j.scitotenv.2020.140074, 2020.
Manheim, F. T., Krantz, D. E., and Bratton, J. F.: Studying Ground Water
Under Delmarva Coastal Bays Using Electrical Resistivity, Groundwater, 42, 1052–1068, https://doi.org/10.1111/j.1745-6584.2004.tb02643.x, 2004.
Maurya, P. K., Christiansen, A. V., Pedersen, J. B., and Auken, E.: High
resolution 3D subsurface mapping using a towed transient electromagnetic
system – tTEM: case studies, Near Surf. Geophys., 18, 249–259, https://doi.org/10.1002/nsg.12094, 2020.
Meier, H., Edman, M., Eilola, K., Placke, M., Neumann, T., Andersson, H. C.,
Brunnabend, S.-E., Dieterich, C., Frauen, C., and Friedland, R.: Assessment
of uncertainties in scenario simulations of biogeochemical cycles in the
Baltic Sea, Front. Mar. Sci., 6, 46, https://doi.org/10.3389/fmars.2019.00046, 2019.
Micallef, A., Person, M., Haroon, A., Weymer, B. A., Jegen, M., Schwalenberg, K., Faghih, Z., Duan, S., Cohen, D., and Mountjoy, J. J.: 3D characterisation and quantification of an offshore freshened groundwater system in the Canterbury Bight, Nat. Commun., 11, 1–15, 2020.
Minsley, B. J., Rigby, J. R., James, S. R., Burton, B. L., Knierim, K. J.,
Pace, M. D. M., Bedrosian, P. A., and Kress, W. H.: Airborne geophysical surveys of the lower Mississippi Valley demonstrate system-scale mapping of
subsurface architecture, Commun. Earth Environ., 2, 131, https://doi.org/10.1038/s43247-021-00200-z, 2021.
Mollidor, L., Tezkan, B., Bergers, R., and Löhken, J.: Float-transient
electromagnetic method: in-loop transient electromagnetic measurements on Lake Holzmaar, Germany, Geophys. Prospect., 61, 1056–1064,
https://doi.org/10.1111/1365-2478.12025, 2013.
Munk, L., Hynek, S., Bradley, D. C., Boutt, D., Labay, K. A., and Jochens,
H.: Lithium brines: A global perspective: Chapter 14, Econ. Geol., 18, 339–365, https://doi.org/10.5382/Rev.18.14, 2016.
Nyboe, N. S. and Sørensen, K. I.: Noise reduction in TEM: Presenting a
bandwidth- and sensitivity-optimized parallel recording setup and methods for adaptive synchronous detection, Geophysics, 77, E203–E212, 2012.
Ong, J. B., Lane, J. W., Zlotnik, V. A., Halihan, T., and White, E. A.:
Combined use of frequency-domain electromagnetic and electrical resistivity
surveys to delineate near-lake groundwater flow in the semi-arid Nebraska Sand Hills, USA, Hydrogeol. J., 18, 1539–1545, https://doi.org/10.1007/s10040-010-0617-x, 2010.
Parsekian, A. D., Singha, K., Minsley, B. J., Holbrook, W. S., and Slater, L.: Multiscale geophysical imaging of the critical zone, Rev. Geophys., 53, 1–26, https://doi.org/10.1002/2014RG000465, 2015.
Pihlainen, S., Zandersen, M., Hyytiäinen, K., Andersen, H. E., Bartosova, A., Gustafsson, B., Jabloun, M., McCrackin, M., Meier, H. M., and Olesen, J. E.: Impacts of changing society and climate on nutrient loading to the Baltic Sea, Sci. Total Environ., 731, 138935, https://doi.org/10.1016/j.scitotenv.2020.138935, 2020.
Rey, D. M., Walvoord, M. A., Minsley, B., Rover, J., and Singha, K.: Investigating lake-area dynamics across a permafrost-thaw spectrum using
airborne electromagnetic surveys and remote sensing time-series data in Yukon Flats, Alaska, Environ. Res. Lett., 14, 025001, https://doi.org/10.1088/1748-9326/aaf06f, 2019.
Rumph Frederiksen, R. and Molina-Navarro, E.: The importance of subsurface
drainage on model performance and water balance in an agricultural catchment
using SWAT and SWAT-MODFLOW, Agr. Water Manage., 255, 107058,
https://doi.org/10.1016/j.agwat.2021.107058, 2021.
Sandersen, J. F.: Kortlægning af begravede dale i Danmark, Opdatering 2015, GEUS Særudgivelse, http://begravededale.dk/PDF_2015/091116_Rapport_Begravede_dale_BIND_1_Endelig_udgave.pdf
(last access: 27 May 2022), 2016.
Sheets, R. and Dumouchelle, D.: Geophysical Investigation Along the Great
Miami River From New Miami to Charles M. Bolton Well Field, Cincinnati, Ohio, US Geological Survey, https://doi.org/10.3133/ofr20091025, 2009.
Siemon, B., Christiansen, A. V., and Auken, E.: A review of helicopter-borne
electromagnetic methods for groundwater exploration, Near Surf. Geophys., 7, 629–646, 2009.
Sophocleous, M.: Interactions between groundwater and surface water: the state of the science, Hydrogeol. J., 10, 52–67, 2002.
Viezzoli, A., Auken, E., and Munday, T.: Spatially constrained inversion for
quasi 3D modelling of airborne electromagnetic data – an application for
environmental assessment in the Lower Murray Region of South Australia, Explor. Geophys., 40, 173–183, 2009.
Winter, T. C., Harvey, J. W., Franke, O. L., and Alley, W. M.: Ground Water
and Surface Water A Single Resource, US Geological Survey, 1139, https://doi.org/10.3133/cir1139, 1998.
Short summary
In this paper, we present an application of the electromagnetic method to image the subsurface below rivers, lakes, or any surface water body. The scanning of the subsurface is carried out by sailing an electromagnetic sensor called FloaTEM. Imaging results show a 3D distribution of different sediment types below the freshwater lakes. In the case of saline water, the system is capable of identifying the probable location of groundwater discharge into seawater.
In this paper, we present an application of the electromagnetic method to image the subsurface...
