Abstract
During the time interval 2003–2005 a ground survey of the total magnetic field intensity in the middle-northern part of Croatia was performed, in order to get a detailed insight of the field distribution over the region. A special effort was done to understand the uncertainty and errors in data reduction, namely different amplitudes of the diurnal variations and different secular variations at the ground stations with respect to the observatories. For data reduction to epoch 2004.5 the total field recordings from AQU, FUR, NCK and THY geomagnetic observatories have been used. We estimate the mean determination error to be one order of magnitude smaller than the maximal reduction error. Multiple linear regression and the method of empirical orthogonal functions were applied on the ground survey and observatory time series. This allowed us to explain the correlations among them and the variance of the total field. Furthermore, we identified two sources of serious artificial disturbances caused by DC leakage: the tramway system of the capital and one railway station in neighbouring Slovenia. Also, we estimate the region free of these disturbances. The magnitude of one of them is estimated to be more than five nT at the distance of about 10 km.
Similar content being viewed by others
References
Andriambahoaka Z., Schott J.J. and Ranaivonomenjanahary F., 2007. Repeat station data reduction using the CM4 model. Publ. Inst. Geophys. Pol. Acad. Sci., C-99(398), 242–249.
Barton C.E. and Newitt L.R., 1995. Regional Magnetic Survey, Chart, and Model Descriptions. Australian Geological Survey Organisation, Canberra, ACT, Australia.
Bendat J.S. and Piersol A.G., 2000. Random Data: Analysis and Measurement Procedures. John Wiley & Sons Inc., USA.
Blakely R.J., 1996. Potential Theory in Gravity and Magnetic Applications. Cambridge University Press, Cambridge, UK.
Campbell W.H., 1989. The regular geomagnetic-field variations during quiet solar conditions. In Jacobs J.A. (Ed.), Geomagnetism, Vol. 3. Academic Press, San Diego, USA, 385–460.
Chambodut A. and Mandea M., 2005. Evidence for geomagnetic jerks in comprehensive models. Earth Planets Space, 57, 139–149.
Cueto M., McKnight D. and Herraiz M., 2003. Daily geomagnetic variations on the Iberian Peninsula. Geophys. J. Int., 152, 113–123.
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.
Jankowski J. and Sucksdorff C.,1996. Guide for Magnetic Measurements and Observatory Practice. International Association of Geomagnetism and Aeronomy (http://www.iugg.org/IAGA/iaga_pages/pdf/IAGA-Guide-Observatories.pdf).
Joselyn J.A., 1989. Geomagnetic quiet day selection. Pure Appl. Geophys., 131, 333–341.
Korte M. and Thébault E., 2007. Geomagnetic repeat station crustal biases and vectorial anomaly maps for Germany. Geophys. J. Int., 170, 81–92.
Lowes F.J., 1987. Magnetic monitoring of DC electric railways. Phys. Technol., 18, 209–214.
Lötter C.J., 1987. Stable inversions of MAGSAT data over the geomagnetic equator by means of ridge regression. J. Geophys., 61, 77–81.
Mandea M. and Purucker M, 2005. Observing, modeling and interpreting magnetic fields of the solid Earth. Surv. Geophys., 26, 415–459.
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.
Newitt L.R., Barton C.E. and Bitterly J., 1996. Guide for Magnetic Repeat Station Surveys, International Association of Geomagnetism and Aeronomy (http://www.iugg.org/IAGA/iaga_pages/pdf/IAGA-Guide-Repeat-Stations.pdf).
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, USA.
Riddihough R.P., 1971. Diurnal corrections to magnetic surveys — an assessment of errors. Geophys. Prospect., 19, 551–567.
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.
St-Louis B. (Ed.), 2004. Intermagnet Technical Reference Manual (Version 4.2.). (http://www.intermagnet.org).
Tokumoto T. and Tsunomura S., 1984. Calculation of magnetic field disturbance produced by electric railway. Memoirs of the Kakioka Magnetic Observatory, 20(2), 33–44 (in Japanese, English translation at http://www.kakioka-jma.go.jp/publ/tr/2004/trs0005.pdf).
Torta J.M., Curto J.J. and Bencze P., 1997. Behaviour of the quiet day ionospheric current system in the European region. J. Geophys. Res., 102(A2), 2483–2494.
Verbanac G. and Korte M., 2006. The geomagnetic field in Croatia. Geofizika, 23(2), 105–117.
Verbanac G., Korte M. and Mandea M., 2007. On long-term trends of the European geomagnetic observatory biases. Earth Planets Space, 59, 685–695.
Von Storch H. and Navarra A., 1999. Analysis of Climate Variability. Springer-Verlag, Heidelberg, Berlin, Germany.
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.
Wardinski I. and Mandea M., 2006. Annual and semi-annual variations of the geomagnetic variations of the geomagnetic field components analysed by the multi-taper method. Earth Planets Space, 58, 785–791.
Yanagihara K., 1977. Magnetic field disturbance produced by electric railway. Geophys. Mag., 38, 17–34.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Vujić, E., Verbanac, G., Vujnović, V. et al. Detailed analysis of the geomagnetic ground survey performed in middle-northern Croatia over the time interval 2003–2005. Stud Geophys Geod 53, 497–517 (2009). https://doi.org/10.1007/s11200-009-0036-4
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11200-009-0036-4