These images are from a report on last night’s NHK evening news. The point was that, in addition to strong waves with a frequency of about 1 to 2 seconds each, Nishihara also experienced waves with frequencies as long as 4 seconds – the strongest such waves ever recorded in an inland area in Japan. The results were devastating for rural Nishihara but the NHK report indicates that such waves are particularly dangerous in areas with high-rise buildings because longer wave frequencies are more likely to “resonate” with tall buildings. The shaking in Nihihara exceeded the design standards for most high-rise buildings in Japan by a factor of three.
– Kirk
P.S. For a limited time, the following link should take you to the video and Japanese text NHK prepared for this segment.
http://www3.nhk.or.jp/news/html/20160514/k10010521261000.html