The present tectonics of Northeast Asia has been extensively investigated during the last 12 yr by using GPS techniques. Nevertheless, crustal velocity field of the southeast of Russia near the northeastern boundaries of the hypothesized Amurian microplate has not been defined yet. The GPS data collected between 1997 February and 2009 April at sites of the regional geodynamic network were used to estimate the recent geodynamic activity of this area. The calculated GPS velocities indicate almost internal (between network sites) and external (with respect to the Eurasian tectonic plate) stability of the investigated region. We have not found clear evidences of any notable present-day tectonic activity of the Central Sikhote-Alin Fault as a whole. This fault is the main tectonic unit that determines the geological structure of the investigated region. The obtained results speak in favour of the existence of a few separate blocks and a more sophisticated structure of the proposed Amurian microplate in comparison with an indivisible plate approach

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Crustal kinematic characteristics such as strain and displacement rates are important in the monitoring of present-day processes in zones of seismic and industrial hazard. Strain measurements on different temporal and spatial baselines reveal potentially hazardous zones. Data on coseismic displacements and strain can be used to refine earthquake models, and long-term characteristics are important in searching for earthquake precursors and studying the rheology of the crust and fault zones. Tilt measurements in the adit of the Talaya seismic station (51.68° N, 103.64° E, South Baikal region) began in 1985; strain measurements, in 1990; and GPS measurements, in 2000. The data reflect time variation in the local strain parameters and permit a comparison with the GPS data on the region and western Central Asia. The data on strain variations obtained in the Ala-Archa underground observatory (42.63° N, 74.50° E, North Tien Shan) are analyzed together with those obtained in the region by GPS methods. Strain rates on very long baselines were determined using data from permanent IGS stations for Central Asia—the territory expanding from Dzungaria in the south to the Siberian Platform in the north and from the Tien Shan in the west to Lake Baikal in the east. We consider the example of using strain gaging and GPS data to construct a dislocation model and refine the parameters of the Kultuk earthquake (South Baikal region, 27 August 2008, M = 6.3).

The recent geodynamics of the Far East region of Russia is considered, where three large tectonic plates converge—Eurasian, North American, and Pacific, as well as several microplates—Okhotsk, Bering, and Amurian—have been hypothesized to exist. The available data on the position of the plate boundaries, the relative plate rotation poles, and the regional seismicity were analyzed, and parameters of plate motion models for northeastern Russia were determined in this study. The regional deep structure was investigated, using data obtained by different geophysical methods. The results of observations of the Magadan–Vrangel Island profile by deep seismic sounding (DSS), common-depth point (CDP) method, and correlation refraction method (CRM) are presented.