Last December, the UN General Assembly passed a unanimous resolution to recognize November 5 as World Tsunami Awareness Day. The Japanese government took initiative of its adoption, in tribute to the episode of “Inamura-no-Hi”: On November 5, 1854 (of old calendar) during the Edo period, a great tsunami occurred after the Ansei Nankai earthquake. They say that Goryo Hamaguchi, a businessman of present-day Hirokawa Town in Wakayama Prefecture, realized the real danger of the tsunami and set fire ...

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After the urgent field survey from April 15, Professor Shinji Toda, together with other researchers, went to Kumamoto again to continue their research from April 22 to 25. As a result, a normal faulting rupture was also discovered in the Futagawa fault zone, and it indicates that an oblique slip occurred deep underground but a strike-slip fault and a normal fault running parallel approximately two kilometers apart on the earth’s surface were identified.   According to the survey...

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Responding to the 2016 Kumamoto Earthquake, Tohoku Block DMAT has been carrying out medical assistance in the areas affected by the disaster. Assistant Professor Hiroyuki Sasaki of IRIDeS went to the site as a member of Tohoku University Hospital DMAT (disaster medical assistance team) which is one of the teams in Tohoku Block DMAT, and took part in activities from April 17 – 19. DMAT is a team of medical professionals, consisting of doctors, nurses and logistics experts who have gone throu...

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Professor Shinji Toda, an expert on active faults in IRIDeS, calculated stress changes (changes in deformation before and after earthquakes) in the surrounding regions and faults after the magnitude 6.5 and 7.3 earthquakes, to find out the mechanism behind aftershocks which have been striking a wide area since April 16. In the figures below, stress is increasing in areas that are marked red, meaning fault activity may be induced, while regions marked in blue are places where stress is decreasing...

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In this field survey, it became clear that from the magnitude 7.3 earthquake on April 16, surface earthquake faults were identified along part of the Futagawa fault zone and in the northern part of the Hinagu fault zone, emerging on the surface. During the survey, a maximum of approximately two meters right-lateral strike-slip in the Futagawa fault zone was measured, while in the northern section of the Hinagu fault zone, a maximum of approximately 50 centimeter right-lateral strike-slip wa...

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