Lithosphere of the Northeastern Part of the Sarmatia Protocraton According to New Seismic Data

Deep velocity models of the lithosphere of the Khoper Block and Losevskaya Suture Zone of the Voronezh crystalline massif of the Sarmatia Protocraton are obtained for the first time by the receiver function technique. The crust is determined by a four-layered structure with a waveguide in the lower part of the section. The presence of a zone of lower velocities in the upper mantle at depths of 110–150 km, which mark the mid-lithospheric discontinuity (MLD), as well as their characteristics, is identified for the first time for the Khoper Block. A complex, probably, gradient structure of the crustal–mantle transition is determined.