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Abstract

A 2-D profile for the shear wave velocity and anisotropy between Egypt and Spitsbergen is presented. The profile is constructed using fundamental- and higher-mode Love and Rayleigh waves recorded by stations of the NARS-DEEP, IRIS and GEOFON networks. The surface wave data have been inverted for shear velocity and anisotropy using a waveform inversion. In the eastern Mediterranean lithosphere we observe a large difference (7 per cent) between SH and SV velocities. We interpret this anomaly as an anisotropic oceanic lithosphere beneath the eastern Mediterranean, an interpretation which is consistent with tectonic reconstructions of the region. The east European continent is imaged as a high-velocity body whose thickness increases with the estimated age of the lithosphere. The continental root of the Ukrainian and Baltic shields and east European platform extends to a depth of 200 km. This is in contrast to the surrounding younger continental regions which appear to be less than 100 km thick. We further studied the structure of the continental lithosphere by investigating a possible relation between seismic velocities and tectonic age. Both a logarithmic and a square root relation have been fitted to the average seismic velocities in each tectonic region. The data slightly favour a logarithmic relation but a square root relation cannot be excluded.