Studia Geophysica et Geodaetica

, Volume 55, Issue 1, pp 175–190 | Cite as

Estimation of the normal geomagnetic field and geological interpretation of the normal field anomalies over middle-northern Croatia

  • Eugen VujićEmail author
  • Giuliana Verbanac
  • Stanislav Francisković-Bilinski
  • Vladis Vujnović
  • Antun Marki


Based on the ground survey of total-field magnetic data at 53 sites, which recorded a time-series over the interval 2003–2005, the core field + long wavelength lithospheric field over the middle-northern Croatia region was calculated. The area of the survey was 18900 km2, an average distance between the neighbouring sites being 12 km. The results were reduced to 2004.5 epoch. This “normal” total-field was estimated using the firstorder Taylor polynomial as a function of geographic coordinates, and the polynomial coefficients were calculated with three methods of adjustment: simple and weighted least squares fits and adjustment according to the most frequent value. The stability of the normal field was tested using the Monte Carlo-type test, by decreasing the input data set in each adjustment (up to 90%). All obtained field residuals (measured-“normal”) were mutually compared, as well as fit coefficients of the Taylor polynomials. The residual values indicate the presence of shorter-wavelength anomalies, specifically three major residual anomalies were found (−106 nT, 74 nT and 57 nT). The geostatistical analysis of the ground survey data and the normal field residuals (respectively), using the median absolute deviation method, was further conducted in order to evaluate the calculated anomalies. The geological situation around the anomalies derived by the median absolute deviation method, and around the normal field residual anomalies, is given. The correlation was found between higher value anomalies of the normal field residuals, and shallow volcanic rocks and oil field, respectively.


ground total-field data normal geomagnetic field geological interpretation of geomagnetic anomalies 


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  1. Bullard E.C., 1967. The removal of trend from magnetic surveys. Earth Planet. Sci. Lett., 2, 293–300.CrossRefGoogle Scholar
  2. Chiappini M., De Santis A., Dominici G. and Torta J.M., 1999. A normal reference field for the Ionian Sea area. Phys. Chem. Earth A, 24, 433–438.CrossRefGoogle Scholar
  3. De Santis A., Chiappini M., Dominici G. and Meloni A., 1997. Regional geomagnetic field modelling: the contribution of the Istituto Nazionale di Geofisica. Annal. Geophys., 40, 1161–1169.Google Scholar
  4. De Santis A., Gaya-Pique L., Dominici G., Meloni A., Torta J.M. and Tozzi R., 2003. Italian Geomagnetic Reference Field (ITGRF): update for 2000 and secular variation model up to 2005 by autoregressive forecasting. Annal. Geophys., 46, 491–500.Google Scholar
  5. Eventov L., 1997. Applications of magnetic methods in oil and gas exploration. The Leading Edge, 16, 489–492.CrossRefGoogle Scholar
  6. Fais S., Klingele E.E. and Tocco R., 1994. Geophysical interpretation of the Gallura magnetic anomaly (northeast Sardinia, Italy). Tectonophysics, 233, 125–144.CrossRefGoogle Scholar
  7. Kovacs P. and Kormendi A., 1999. Geomagnetic repeat station survey in Hungary during 1994–1995 and the secular variation of the field between 1950 and 1995. Geophysical Transactions, 42, 107–132.Google Scholar
  8. Kovacs P., Kormendi A., Hegymegy L., Chiappini M. and Dominici G., 1999. The Hungarian magnetic network and the processing of the obtained data. Phys. Chem. Earth A, 24, 439–443.CrossRefGoogle Scholar
  9. Kugler A., 1916. Geomagnetic research in Croatia in 1916. Vijesti geološkog povjerenstva za Kraljevinu Hrvatsku i Sloveniju, za god. 1914. i 1915, Sv. 5 i 6, 100–110 (in Croatian).Google Scholar
  10. Linsser H., 1970. Remarks on the use of the magnetic gradiometer in oil exploration. Geophys. Prospect., 18, 119–133.CrossRefGoogle Scholar
  11. Lötter C.J., 1987. Stable inversions of MAGSAT data over the geomagnetic equator by means of ridge regression. J. Geophys., 61, 77–81.Google Scholar
  12. Mandea M. and Purucker M, 2005. Observing, modeling and interpreting magnetic fields of the solid Earth. Surv. Geophys., 26, 415–459.CrossRefGoogle Scholar
  13. Manoj C., Kuvshinov A., Maus S. and Lühr H., 2006. Ocean circulation generated magnetic signals. Earth Planets Space, 58, 429–437.Google Scholar
  14. Meloni A., Battelli O., De Santis A. and Dominici G., 1994. The 1990.0 magnetic repeat station survey and normal reference fields for Italy. Annal. Geophys., 37, 949–967.Google Scholar
  15. Newitt L.R., Barton C.E. and Bitterly J., 1996. Guide for Magnetic Repeat Station Surveys. International Association of Geomagnetism and Aeronomy, ISBN: 0-9650686-1-7.Google Scholar
  16. Press W.H., Teukolsky S.A., Vetterling W.T. and Flannery B.P., 2001. Numerical Recipes in Fortran 77: The Art of Scientific Computing. Cambridge University Press, Cambridge, U.K.Google Scholar
  17. Reimann C., Filzmoser P. and Garrett R.G., 2005. Background and threshold: critical comparison of methods of determination. Sci. Total Environ., 346, 1–16.CrossRefGoogle Scholar
  18. Routh P.S., Lyle M., Hess S. and Bradford J., 2006. 3D Magnetic characterization of hot springs in a hydrothermal system in the Alvord Basin, Oregon. GRC Transactions, 30, 937–940.Google Scholar
  19. Sabaka T., Olsen N. and Purucker M., 2004. Extending comprehensive models of the Earth’s magnetic field with Oersted and CHAMP data. Geophys. J. Int., 159, 521–547.CrossRefGoogle Scholar
  20. Sikošek B., 1971. Geological Map of SFRJ 1:500000. Savezni geološki zavod, Beograd, Serbia (in Croatian).Google Scholar
  21. Soengkono S. and Hochstein M.P., 1995. Application of magnetic method to assess the extent of high temperature geothermal reservoirs. Proceedings, Twentieth Workshop on Geothermal Reservoir Engineering. Stanford University, California, 71–78 ( Scholar
  22. Steiner F., 1988. Most frequent value procedures. Geophys. Trans., 34, 139–260.Google Scholar
  23. Thébault E., Mandea M. and Schott J.J., 2006. Modeling the lithospheric magnetic field over France by means of revised spherical cap harmonic analysis (R-SCHA). J. Geophys. Res., 111, 949–967.Google Scholar
  24. Tukey J.W., 1977. Exploratory Data Analysis. Addison-Wesley, Reading, MA.Google Scholar
  25. Verbanac G. and Korte M., 2006. The geomagnetic field in Croatia. Geofizika, 23, 105–117.Google Scholar
  26. Vujić E., Verbanac G., Vujnović V. and Marki A., 2009. Detailed analysis of the geomagnetic ground survey performed in middle-northern Croatia over the time interval 2003–2005. Stud. Geophys. Geod., 53, 497–517.CrossRefGoogle Scholar
  27. Vujnović V., Verbanac G., Orešković J., Marki A., Marić K., Lisac I. and Ivandić M., 2004. Results of the preliminary geomagnetic field strength measurements in the northern part of middle Croatia. Geofizika, 21, 69–87.Google Scholar
  28. Xu W.J., Xia G.H., An Z.C., Chen G.X., Zhang F.Y., Wang Y.H., Tian Y.G., Wei Z.G., Ma S.Z., and Chen H.F., 2003. Magnetic Survey and ChinaGRF 2000. Earth Planets Space, 55, 215–217.Google Scholar

Copyright information

© Institute of Geophysics of the ASCR, v.v.i 2011

Authors and Affiliations

  • Eugen Vujić
    • 1
    Email author
  • Giuliana Verbanac
    • 1
  • Stanislav Francisković-Bilinski
    • 2
  • Vladis Vujnović
    • 1
  • Antun Marki
    • 1
  1. 1.Department of Geophysics, Faculty of SciencesUniversity of ZagrebZagrebCroatia
  2. 2.Institute “Ruđer Bošković”ZagrebCroatia

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