Experience of Complex Microseismic and Magnetotelluric Sounding on the Northern Part of the Central Sikhote-Alin Fault

Abstract

We present the results of a study of the crustal structure of the northern part of the Central Sikhote-Alin Fault (CSAF) by methods of microseismic sounding (MSS) and magnetotelluric sounding (MTS). A geoelectric section based on MTS data and a section of relative velocities of P-waves according to MSS data were constructed and interpreted at a depth of up to 9 km and a length of 42 km. The main blocks, their boundaries, fault zones and some anomaly zones identified by microseismic and magnetotelluric sounding practically coincide. The CSAF zone is expressed by a narrow subvertical zone between high resistivity blocks. The data obtained indicate that the fault zone in the study area is impermeable. A similar structure was identified 6 km northwest of the CSAF zone, which can be traced to twice the depth (up to 20 km). It is concluded that the combination of microseismic and magnetotelluric sounding methods is promising for studying the structure of the Earth's crust in fault zones.