Earthquake in Western Yamaguchi Prefecture on July 11

Earthquake in Western Yamaguchi Prefecture on July 11

On July 11, 2006, at 03:09 (JST) there was a M4.0 earthquake at a depth of 16km in western Yamaguchi prefecture (maximum seismic intensity 3). The focal mechanism showed a strike-slip fault with a compression axis in an E-W direction. The major aftershock activity subsided within a day, and subsequently there were intermittent small aftershocks observed. (Figure A)

For the seismic activity since August 1923, there was a M6.0 earthquake on October 28, 1991 in the vicinity of the recent event.
In addition, there were no historically significant recorded earthquakes along the Kikukawa fault zone. (Figure B)

Japan Meteorological Agency
[Seismic Activity for July 2006 (August 9, 2006)]