“It’s Complicated”: Japan aftershock upgraded to M7.4 — Gov’t now says it was 2 quakes at same time
Source: Asahi Shimbun Digital
Summary Translation: Fukushima Diary
Date: Dec. 11, 2012
[...] Earthquake Research Committee of the government announced it was two continuous earthquakes which are separated. According to the analysis of meteorological agency and Earthquake Research Institute of the University of Tokyo, the first earthquake was reverse fault type from the inside of the pacific plate, and 10~20 seconds later, the second one occurred, which was normal fault type. Japan meteorological agency comments it was really a complicated mechanism.