SEISMICITY of THE NORTH-EAST of RUSSIA in 2020

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The results of seismic monitoring of the Magadan region, Chukotka Autonomous Area and the shelf of adjacent seas (Okhotsk, Chukchi, Bering and East Siberian seas) are considered. There were 12 working seismic stations in the region. The catalog of the Russian North-East earthquakes for 2020 includes information about 327 earthquakes, 114 of them are out of the region and 213 with energy classes KR=6.2–12.2 are within the region borders. As usual, most of 213 regional earthquakes (80 %) are localized in the Kolyma area. The total seismic energy released within the region’s borders was equal ΣЕ=3.4481012 J. The classification of Russian North-East earthquakes was performed using energy classes KР of T.G. Rautian’s scale. The energy representa tiveness map of earthquakes with Кmin=6–10 was built. The Magadan network of stations records without omis sions the earthquakes with Kmin=7 in Magadan oblast, with Kmin=8 in Okhotsk sea, Kmin=10 in the Chukchi. The strongest earthquake of 2020 with KR=12.2 (mb=4.3, Ms=3.7) occurred on November 1, 11h44m in the Bering Sea. Epicenters of Magadan region earthquakes were plotted on the tectonic zoning scheme. Most earthquakes are confined to the largest deep faults in the northwestern and sublatitudinal directions. All hypocenters are located within the earth's crust. In 2020, the seismicity level of the North-East of Russia according to the “SOUS09” scale was assessed as "background average" for the observation period from 1968 to 2020. Spatially, all Russian North-East earthquakes are traditionally con centrated in large seismogenic belts: Chersky, North-Okhotsk and Trans-Beringian.