Tohoku Region

# A dotted line shows the aftershock area of the 2011 off the Pacific Coast of Tohoku Earthquake.

a) During November, within the aftershock area of the 2011 off the Pacific Coast of Tohoku Earthquake, there were 4 earthquakes of M5.0 or over and one earthquake of M6.0 or over. There were one earthquake with a maximum seismic intensity 4 and one earthquake with a maximum seismic intensity 5 Upper, respectively. In addition, there were seismic activities of b) and e) in the following.
b) Since March 11, 2011, seismic activities have been brisk within the crust from Hamadori, Fukushima prefecture through northern Ibaraki prefecture. On November 20, there were a M5.3 earthquake (maximum seismic intensity 5 Upper) and a M4.8 earthquake (maximum seismic intensity 3) in northern Ibaraki prefecture.
c) Since March 18, a series of seismicity with M3.0 or so has been seen within the crust from Aizu, Fukushima prefecture through the Okitama region, Yamagata prefecture. As of late November, it continues.
d) On November 10, there was a M4.1 earthquake (maximum seismic intensity 4) in the southern inland, Akita prefecture.
e) On November 24, there was a M6.1 earthquake (maximum seismic intensity 4) offshore Fukushima prefecture.

J-EGG500 from the Japan Oceanographic Data Center, GTOPO30 from the US Geological Survey, and ETOPO2v2 from the National Geophysical Data Center in the U.S. were used for the topographic and bathymetric data.

[Earthquake(s) mentioned have one or more of the following features: M6.0 or greater or maximum seismic intensity 4 or greater, M4.5 or greater and maximum seismic intensity 3 or greater on shore, M5.0 or greater and maximum seismic intensity 3 or greater in the ocean area.]

N: total number of events in the figure

Japan Meteorological Agency
Ministry of Education, Culture, Sports, Science and Technology
[Evaluation of Seismic Activities for November 2011 (December 9, 2011)]