Deep seismic structure of the Sikhote-Alin folded system according to the GSZ (in the alignment of the reference profile 8-DV)

Abstract

The results of deep seismic studies on the Sikhote-Alin fragment of the reference geophysical profile 8-DV are presented. A deep seismic section of the Earth's crust and upper mantle with the velocity distribution of longitudinal waves is constructed. The complex dislocated structure of a powerful Paleozoic sedimentary complex within the Middle Amur Depression has been established. Crystalline rocks with longitudinal wave velocities of 6.0-6.2 km/s lie at depths from 8 to 13 km in different parts of the Middle Amur Depression and 4-6 km within the Sikhote-Alin orogenic complex. In the entire thickness of the Earth's crust of the Sikhote-Alin fragment of the 8-DV profile, the velocities of longitudinal waves are 6.3-6.35 km/s. The thickness of the Earth's crust varies from 32 to 35 km. Along the Mohorovichich boundary, the velocity of longitudinal waves in general is 7.8-8.3 km/s. The correlation of the identified anomalies according to P-wave data with structural-tectonic zones was carried out.