LUCIAN BESUTIU
(ABSTRACT)
The paper deals with problems related to the normal geomagnetic field (ngf)
concept within confined areas. Both spherical harmonic and polynomial regression
based ngf models for the Romanian territory have been performed and compared
for various magnetic epochs trying to decode their limits and geological
support. The analysis clearly showed that local spherical harmonic ngf models
are strongly affected by regional circumstances. Compared to the spherical
harmonic models, ngf models constructed as second order polynomials proved
to be close to the field of the equivalent geomagnetic eccentric dipole (n
= 2), except for a residual anomaly located in central Romania. Increasing
deviations toward the state border, due to the neglecting of the Earth’s
curvature, were also evidenced.
Key words: geomagnetism, normal field, anomaly, harmonic analysis, polynomial
regression