DEVELOPMENT OF GPS TECHNOLOGIES IN THE AREA OF THE TUAPSE-SOCHI SEISMIC ZONE, TAKING INTO ACCOUNT THE FAULT-BLOCK STRUCTURE

Data of movements of seismically active sections of the Earth’s crust in the area of the Black Sea coast are given according to GPS measurements, which were continuously carried out from 6 to 9 years in the regional network of satellite geodynamic stations GPS/GLONASS (SGS). The network includes two segments covering the northwestern and southeastern parts of the Azov-Black sea coast of the Krasnodar Region. Background values of earth crust deformations required for instrumental assessment of stress state of geological environments during earthquake preparation are determined. Observations on the SGS of the eastern segment of the Sochi, Adler, Lesnoe and Esto-Sadok network, located within the Pshekh-Adler transverse flexure-fault zone, confirmed the geodynamic activity of the most seismically dangerous Mzymta fault from the Krasnaya Polyana region to its interface with the deep Plastunsky fault. GPS observations and seismic data established the geodynamic activity of the lower valley region of the Mzymta River, covered with a series of faults and fracture zones limited by sub-latitudinal faults that determine the main geotectonic zonality of the Caucasus with the possible continuation of geodynamic activity of this region in the sea until the intersection with the East Black Sea fractured zone. As a result of synchronous GPS measurements at the permanent Esto-Sadok SGS and the periodic SGS Aibga with a height difference of 1700 m a diverse pattern of movements was established and a left-hand shift along the Mzymta fault was confirmed. In the west of the Tuapse-Sochi seismic zone, observations on the periodic SGS Chemitokvadzhe revealed the geodynamic activity of cross-sectional (anti-Caucasian) faults. Monitoring of seismogeodynamic activity of these faults additionally requires installation of permanent SGS in the area of Tuapse, Chemitokvadzhe and Golovinka settlements. A longer period of continuous observations at GPS stations (25–30 years) will make it possible to detect a change in geodynamic compression and stretching periods of the crust, which is important to assess the geodynamic situation during the construction of long-term objects of increased responsibility and determine the seismic hazard precursors.

GPS observation, crust deformation, earthquake precursors, Caucasus