Earthquake Offshore Iwate Prefecture on February 2
On February 2, 2016 at 14:31 (JST), there was a M5.6 earthquake (maximum seismic intensity 4) at a depth of 22 km, offshore Iwate prefecture. The focal mechanism (CMT solution) showed a normal fault type with a tension axis in an NNW-SSE direction.
For the seismic activity since October 1997, in the vicinity of the recent event (Area b), there was only 1 earthquake of M5.0 over, before the occurrence of "the 2011 off the Pacific Coast of Tohoku Earthquake." But just after that earthquake, seismic activity became tentatively high: several earthquakes of M5.0 over.
For the seismic activity since January 1923, in the area around the recent event (Area c), there have sometimes been earthquakes of M6.0 over.
[Evaluation of Seismic Activities for January 2016 (February 9, 2016)]