ANDREI SOARE1, GABRIELA CUCU1, MIOARA MANDEA ALEXANDRESCU2
1Institut Géologique de Roumanie
2Institut de Physique du Globe de Paris, France
Long periods of the geomagnetic field in Romania. Long time series were obtained for three important Romanian cites (Bucharest, Jassy and Cluj), using large extended geomagnetic data, consisting in the historical geomagnetic measurements made in the last two centuries and the most recent mean values deduced from the Surlari geomagnetic recordings. The spectral analysis of the data emphasizes some components of the secular variation with a period range of decades, which are also mentioned at other old European observatories. The study of such spectral analysis on extended areas can provide supplemental information about the low-mantle electric conductivity, the external-core convection currents and also about some geodynamic problems.
Key words: geomagnetic elements, long time series, secular variation.