New Magnetotelluric Data for the Fennoscandia–Sarmatia Suture Zone

Abstract—The results of magnetotelluric soundings obtained in 2020 along the Rzhev–Velikie Luki profile in the suture zone of three segments of the Precambrian crust of the East European Platform: Fennoscandia, Sarmatia, and Volga-Ural are presented. An anomaly zone of increased conductivity in the crust was revealed in the central part of the profile. The crust conductor is weakly expressed on the components of the telluric tensor due to the screening effect of the conducting sedimentary cover; therefore, the main emphasis in the qualitative analysis of the data and inversion is placed on magnetovariation parameters. According to the results of 2D inversion carried out in A.E. Kaminsky’s ZONDMY2D program, a subvertical zone of low resistivity has been identified on the geoelectric model in the crust, which is assumed to be associated with a paleosubduction zone of the Belarusian Oceanic Plate.