[1] Regional seismic tomography provides valuable information on the structure of shields, thereby gaining insight to the formation and stabilization of old continents. Fennoscandia (known as the Baltic Shield for its exposed part) is a composite shield for which the last recorded tectonic event is the intrusion of the Rapakivi granitoids around 1.6 Ga. A seismic experiment carried out as part of the European project Svecofennian-Karelia-Lapland-Kola (SVEKALAPKO) was designed to study the upper mantle of the Finnish part of the Baltic Shield, especially the boundary between Archean and Proterozoic domains. We invert the fundamental mode Rayleigh waves to obtain a three-dimensional shear wave velocity model using a ray-based method accounting for the curvature of wave fronts. The experiment geometry allows an evaluation of lateral variations in velocities down to 150 km depth. The obtained model exhibits variations of up to ±3% in S wave velocities. As the thermal variations beneath Finland are very small, these lateral variations must be caused by different rock compositions. The lithospheres beneath the Archean and Proterozoic domains are not noticeably different in the S wave velocity maps. A classification of the velocity profiles with depth yields four main families and five intermediate regions that can be correlated with surface features. The comparison of these profiles with composition-based shear wave velocities implies both lateral and vertical variations of the mineralogy.

The Svecofennian‐Karelian‐Lapland‐Kola Transect (SVEKALAPKO) project is one of the five multidisciplinary key projects of Europrobe, a scientific program of the European Science Foundation (ESF) that studies the tectonic evolution of European continental lithosphere [Gee and Zeyen, 1996]. The SVEKALAPKO project [Hjelt and Daly, 1996] has adopted a multidisciplinary approach that uses geological, penological, and geophysical methods to unravel the evolution of the crust and lower lithosphere in three major crustal segments of the Fennoscandian Shield: the Proterozoic Svecofennian and Lapland‐Kola orogens and the intervening Archaean Karelia craton. Improved knowledge of the structure and evolution of the Fennoscandian Shield should lead to a better understanding of plate‐tectonic processes in the early history of the Earth.

The theoretical relationship between non-local motionally induced voltages (MIV) and tidal currents is validated with observations of natural low-frequency electric field at the coast of the Throat of the White Sea (northwestern Russia). The Throat of the White Sea is a strait of 50-km width and about 500-km length with depths varying from 20 to 50 m connecting semi-closed White Sea basin with the Barents Sea. Strong tidal currents providing a reference signal for calibrating coastal measurements of non-local MIV characterize the Throat. The measurements were carried out simultaneously by means of two horizontal receiving on-land and land-sea antennas. Tidally driven MIV dominates in all time series obtained in the coastal zone of the Throat of the White Sea. Monitoring of non-local MIV within the coastal zone could be used for studies of wind tides, residual tidal circulation and temporal variability of a quasi-stationary current. MIV measurements offer an important advantage over traditional oceanographic methods (currents meters, etc.), because it works also in winter period (about 6 months) when the White Sea is covered by ice. The main disadvantage of this technique is a necessity to calibrate non-local MIV with some other oceanographic direct or remote measurements.

Test measurements of the electric voltage in Kilpisjarvi, northern Finland during September 9-October 12, 1995 were made with the aim of studying the possibility of detecting a motionally induced electric field by means of a horizontal electric dipole 3800 meters in length located at a distance of about 50 km from the nearest fjord of the Norwegian Sea. In addition to the electric voltage we measured at Kilpisjarvi, the water level, magnetic field and meteorological data from Tromsg, Norway, the meteorological data from Kilpisj arvi and the magnetic field data from Sodankyla, Finland were used in analysis. Raw data were preprocessed to eliminate non-stationarities (remove outliers) and to remove solar daily variations, and were then smoothed. No significant influence of the local temperature, humidity and rainfall on the smoothed voltages was found. Probably due to a source effect the voltage was not coherent with the magnetic field from Tromsg and Sodankyla. The long-period anomaly with the period of about 16 days was observed in the smoothed voltage, water level and air pressure. More data are necessary to derive a definite conclusion about the nature of the observed phenomenon, which is probably associated with direct atmospheric forcing on the coastal zone of the Norwegian Sea.

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