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The results of geomagnetic soundings in the West Carpathians are presented. The number of observation sites in this region was approximately 90. The data treatment included the calculation of single-station transfer functions and the separation of the fields into external and internal parts on some profiles. The interpretation was based on the construction of twodimensional models explaining the observed features. The observed distribution of geomagnetic induction vectors is very regular and the axis of the anomaly runs in the contact region between the outer and inner Carpathians.The thickness of the well-conducting rock complex exceeds 10 km. The wellconducting rocks seem to be the sediments which accumulated in the contact region of the platform. The asymmetry in the distribution of induction vector amplitudes on some profiles can be accounted for by asymmetrical geometry, which is characteristic of the underthrusting of rocks.

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The study of peculiarities in the distribution of the electric conductivity within the Earth's crust and in the upper mantle has been carried out as a special contribution to the Five field components of the magnetotelluric field (3 magnetic+2 horizontal electric)were recorded continuously at each station for the period of two months at least. Two recording sets were used to obtain variation data in the range of periods from a few seconds to a few hours.The experimental data were processed by direct reading of the amplitudes of the quasisinusoidal variations such as PC 1 and PC 3, or, by applying the methods of spectral (235)

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Geomagnetic observatory data were analysed to obtain the spectral amplitudes and phases of the 27-day variation and its harmonics over a network of mostly European observatories, but extended to global scale by including some suitably distributed geomagnetic stations on other continents. The spectral amplitudes, estimated by different methods, were subjected to spherical harmonic analysis by expanding the geomagnetic potential function into a series of spherical harmonics up to the 2nd order and by calculating the corresponding coefficients. The contours of the H and Z components were then calculated to analyse their latitude-longitude dependence over European area. The moduli of electromagnetic response functions estimated from global data for individual harmonics were compared with the results obtained previously for European data only. The distribution of deviations of (ZJH) ratios defined by differences between the actual data and the theoretical fits were investigated. Using the theoretical basis of electromagnetic induction in stratified conductors, we estimated the depths of a perfect substitute conductor at those depths from characteristics of the 27-, 13-, and 9-day variations.

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