Velocity Structure of the Upper Mantle of the East European Platform According to Seismic Noise Data

Cross-correlation functions of noise are constructed on 119 interstation paths from seismic noise records at stations of Eastern Europe. Dispersion curves of the group velocity of Rayleigh waves obtained from the cross-correlation functions are used for constructing the three-dimensional distribution of the velocity of transverse waves on the East European platform and in adjacent regions by methods of surface-wave tomography. The mean velocity in the crust is minimum in the region of the Caspian depression and Black Sea basin (< 3.3 km/s) and maximum in the Baltic shield area (> 3.7 km/s). The upper mantle beneath the Baltic and Ukrainian shields is characterized by increased velocity and the absence of the asthenospheric layer. Reduced velocities are noted in the upper mantle of the Black Sea basin. A low-velocity anomaly in the shape of a vertical column is revealed at depths of 200-300 km in the central part of the Dnieper-Donets aulacogen, which confirms the existence of a paleorift in this region.