Assessment of seawater intrusion using geophysical well logging and electrical soundings in a coastal aquifer, Youngkwang-gun, Korea

  • Hwang Seho (Geological & Environmental Hazards Division, Korea Institute of Geoscience and Mineral Resources) ;
  • Shin Jehyun (Geological & Environmental Hazards Division, Korea Institute of Geoscience and Mineral Resources) ;
  • Park Inhwa (Groundwater & Geothermal Resources Division, Korea Institute of Geoscience and Mineral Resources) ;
  • Lee Sangkyu (Korea Institute of Geoscience and Mineral Resources)
  • Published : 2004.02.01


A combination of drilling, geophysical well logging, and electrical soundings was performed to evaluate seawater intrusion in Baeksu-eup, Youngkwang-gun, Korea. The survey area extends for over 24 $km^2$. To delineate the extent of seawater intrusion, 60 vertical electrical soundings (VES) have been carried out. Twelve wells were also drilled for the collection of hydrogeological, geochemical, and geophysical well logging data, to delineate the degree and vertical extent of seawater intrusion. To map the spatial distribution of seawater in this coastal aquifer, geophysical data and hydrogeochemical results were used, and the relation between the resistivity of groundwater and equivalent NaCl concentration was found. Layer parameters derived from VES data, various in-situ physical properties from geophysical well logging, and the estimated equivalent NaCl concentration were very useful for quantitative evaluation of seawater intrusion. Our approach for evaluating seawater intrusion can be considered a valuable attempt at enhancing the use of geophysical data.


  1. Archie, G.E., 1942, The electrical resistivity log as an aid to determining some reservoir characteristics: Trans. AIME., 146, 54-63
  2. Fittennan, D.V., Deszc-Pan, M. and Stoddard, C. E., 1999, Results of time-domain electromagnetic soundings in Everglades National Park, Horida: U.S. GeologicalSurvey Open-File Report, 99-426
  3. Hilchie, D. W., 1984, A new water resistivity versus temperature equation: The Loe Analyst, 25, 20-21
  4. Hwang, S. H., Yun, S. T, Park, I. H., Shin, J. H., Shin, K, S., and Lee, S. K., 2003, Investigation for regional saltwater intrusion of western and southern coastal area in South Korea (Abstract): Proc. 80th Meeting of Korea Soc. Geosys. Eng., 413
  5. Kwader, T, 1985, Estimating aquifer permeability from formation factors: Ground Water, 23, 762-766
  6. Kwader, T., 1986, The use of geophysical logs for determining formation water quality: Ground Water, 24, 11-15
  7. Morin, R.H. and Urish, D.W., 1995, Hydrostratigraphic characterization of a coastal aquifer by geophysical log analysis, Cape Cod National Seashore, Massachusetts: The Log Analyst. 36, 27-37
  8. Nowroozi, A.A., Hon-ocks, S.B., and Henderson, P., 1999, Saltwater intmsion into the freshwater aquifer in the eastern shore of Virginia: a reconnaissance electrical resistivity survey: J. Apptied Geophys., 42, 1-22
  9. Paillet, F.L., Hite, L. and Carlson, M., 1999, Integrating surface and borehole geophysics in groundwater studies - an example using electromagnetic soundings in south Horida: J. Environ. Eng. Geophys., 4, 45-55
  10. Schlumberger Ltd, 1972, Lof interpretation, Vol. 1, Principles'. Schlumberger
  11. Schnoebelen, D.J., Bugliosi, E.F. and Krothe, N.C., 1995, Delineation of saline ground-water boundary from borehole geophysical data: Ground Water, 33,965-976