In 1958, I.V.Litvinenko laid the foundation for seismic studies of the consolidated earth crust on the Baltic Shield: for the first time, depth seismic soundings were performed in Karelia.

To date, extensive data on the seismic properties of the crust-upper mantle boundary have been accumulated in many regions, indicating that ideas about the Mohorovicich (M) surface have changed significantly since the time of its discoverer.

Transverse waves in deep seismic soundings (DSS) in the eastern (Soviet) part of the Baltic Shield were hardly studied until recently because of the insufficient recording time interval of the equipment used.

In 1980 on the Priladozhsky profile (Lahdenpokhya - Lake Segozero) the production-geological association Sevzapgeologia and Problem Research Laboratory of geological-geophysical research of the Baltic Shield of the G.V.Plekhanov Leningrad Mining Institute performed depth seismic sounding (DSS) ...