STRONG EARTHQUAKE SERIES IN SOUTHWEST ALASKA IN 2020–2021: HAS THE SHUMAGIN GAP CLOSED?

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Abstract

The work is focused on the study of a series of strong earthquakes that occurred within and in the nearest vicinity of the Shumagin seismic gap (southwest Alaska) in 2020–2021, based on satellite geodetic data. We constructed models of fault zones of three earthquakes: July 22, 2020 (MW = 7.8), October 19, 2020 (MW = 7.6), and July 29, 2021 (MW = 8.2). The spatial and energy relationships of the fault zones of the occurred earthquakes and the preseismic interplate coupling within the gap are studied. It is shown that only a part of the seismogenic potential accumulated within the Shumagin gap since the beginning of the 20th century was released during the 2020–2021 events.

About the authors

I. S Vladimirova

Shirshov Institute of Oceanology of Russian Academy of Sciences; Federal Research Center "Geophysical Survey of the Russian Academy of Sciences"

Email: vladimirova.is@ocean.ru
Moscow, Russia; Obninsk, Russia

Yu. V Gabsatarov

Shirshov Institute of Oceanology of Russian Academy of Sciences; Federal Research Center "Geophysical Survey of the Russian Academy of Sciences"

Moscow, Russia; Obninsk, Russia

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