Japan is one of the most seismically active countries and this shock was one of several to have struck the North-East this week, including one of magnitude 7.3 on Wednesday.

日本是一个多地震活动的国家。本周发生在东北部地区的这次地震时多起地震中的一个，包括此前，星期三发生的一次里氏7.3级的地震。