Aftershocks remain for half a year at least, and might continue for several years

There was a big quake with a seismic intensity of 6 in Fukushima Prefecture and Ibaraki Prefecture around 5:16 PM on April 11, a month after the March 11th Eastern Japan Great Earthquake. The epicenter was at Hamadori, Fukushima Prefecture with about 6 kilometer deep and size was estimated magnitude 7. One man (46) in Ibaraki died after stumbling. In Iwaki City, Fukushima Prefecture, three houses were collapsed by mudslide and a sixteen-year-old girl died and three people are in serious condition with unconsciousness. At Fukushima Daiichi Nuclear Power Plant, the external power was shut off temporarily. According to the Nuclear and Industrial Safety Agency of the Ministry of  Economy, Trade and Industry, it was restored soon, and there is no problem regarding the safety.


One month has passed since the big earthquake, but recurrent aftershocks are still going on. Ms. Seiko Oki at The Earthquake Research Institute of Tokyo University (Bunkyo Ward, Tokyo) analyzed the situation and advised, “The scale of this earthquake was so enormous that we should expect the recurrence of aftershocks for at least half a year, and it might last for several years in the worst case.”


The institute explains, “The maximum level of the aftershock caused by the magnitude 9 of this earthquake is expected to be magnitude 8 as one grade minus from the original level. The aftershock this time is magnitude 7 and seismic intensity of 6, and we do not know, to tell the truth, if there will be aftershock of magnitude 8 class or not. Aftershocks of magnitude 7 will occur 10 times more than magnitude 8 quakes.” They expect many aftershocks with enormous energy equivalent to Hanshin Awaji Great Earthquake.


The institute also explains that there would be no massive tsunami like the one we had at the original earthquake except off Iwate Prefecture and Chiba Prefecture that are the both ends of the area of hypocenter of the earthquake where the fault was destroyed. They urge people to ensure the safety measures such as reinforcement of quake resistance in buildings, fixing the furniture to prevent from falling, and keeping shoes at the bedside to secure the safe escape. They say that you can survive as long as you eliminate the cause for being crushed. The activation of volcano caused by the earthquake settled within that day, but the monitoring is being continued.


Ms. Oki stressed, “Tokai Earthquake is a great disaster expected to occur with 30 years span. Japanese must think that we’ve entered the different era from the past quiet one hundred years.” She calls for the drastic reform of awareness of the earthquake all over Japan.

Sports Hochi 4/12/2011 06:01, Sports Hochi)

http://hochi.yomiuri.co.jp/topics/news/20110412-OHT1T00033.htm

Translated by Makiko Tajima Asano