Russian Journal of Earth Sciences Russian Journal of Earth Sciences Russian Journal of Earth Sciences 1681-1208 46906 ОРИГИНАЛЬНЫЕ СТАТЬИ ORIGINAL ARTICLES ОРИГИНАЛЬНЫЕ СТАТЬИ Mega-earthquake on 11 March 2011 in Japan and aftershock process dynamics' development Mega-earthquake on 11 March 2011 in Japan and aftershock process dynamics' development Tikhonov I N Tikhonov I N Institute of Marine Geology and Geophysics of Far Eastern Branch of RAS, Yuzhno-Sakhalinsk, Russia ru Institute of Marine Geology and Geophysics of Far Eastern Branch of RAS, Yuzhno-Sakhalinsk, Russia ru 12 1 1 9 10 11 2021 https://rjes.ru/en/nauka/article/46906/view

The article provides data on seismic activity and recurrence periods of strongest (M ge; 7.6 earthquakes for the historical and instrumental periods of observations in epicenter area of a mega-event. It was shown that a period of recurrence of strongest events in this area was about 40 years. To the east of Honshu island a long seismic gap (~800nbsp;km was discovered, located to the south of latitude 39oN and filled recently with aftershocks of the 11.03.2011 mega-earthquake. Significant analogues in aftershocks dynamics of the 2011 Great Japan Earthquake with aftershock sequences of the Sumatra-Andaman 2004, Mw = 9.3 and Simushir 2006, Mw = 8.3 earthquakes were described. A similarity over time for the first event and over space field of aftershocks' epicenters for the second event was noted. The author suggested a possibility of occurrence of a recurrent strong event with magnitude approximately equal to 8, shifted along the main thrust towards the deep oceanic trench.

The article provides data on seismic activity and recurrence periods of strongest (M ge; 7.6 earthquakes for the historical and instrumental periods of observations in epicenter area of a mega-event. It was shown that a period of recurrence of strongest events in this area was about 40 years. To the east of Honshu island a long seismic gap (~800nbsp;km was discovered, located to the south of latitude 39oN and filled recently with aftershocks of the 11.03.2011 mega-earthquake. Significant analogues in aftershocks dynamics of the 2011 Great Japan Earthquake with aftershock sequences of the Sumatra-Andaman 2004, Mw = 9.3 and Simushir 2006, Mw = 8.3 earthquakes were described. A similarity over time for the first event and over space field of aftershocks' epicenters for the second event was noted. The author suggested a possibility of occurrence of a recurrent strong event with magnitude approximately equal to 8, shifted along the main thrust towards the deep oceanic trench.

Large earthquake recurrence of the large earthquakes seismic gap mega-earthquake aftershock sequence strongest aftershock field of aftershocks' epicenters probable scenario Large earthquake recurrence of the large earthquakes seismic gap mega-earthquake aftershock sequence strongest aftershock field of aftershocks' epicenters probable scenario

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