Earthquake Offshore Yamagata Prefecture on June 18, 2019

On June 18, 2019 at 22:22 (JST), there was an M6.7 earthquake (maximum seismic intensity 6 Upper) at a depth of 14 km, offshore Yamagata prefecture.This event occurred within the crust. The focal mechanism showed a reverse fault type with a compression axis in a WNW-ESE direction. JMA announced Tsunami Advisory at 22:24 (JST) for Yamagata prefecture, Joetsu, Chuetsu and Kaetsu, Niigata prefecture, Sadoshima Island and Noto, Ishikawa prefecture (Tsunami Advisory was cancelled at June 19 at 01:02 (JST)). This event caused tsunami observed along the coasts of Akita to Noto, Ishikawa prefectures, such as that of 0.1 m at Niigata. The maximum earthquake after the M6.7 earthquake was a M4.1 (maximum seismic intensity 4) that occurred on 19th at 00:57 (JST).
This event caused damage with 26 injured persons and 46 partially-collapsed houses (as of June 19 at 14:00 (JST), Fire and Disaster Management Agency).
For the seismic activity since October 1997, in the vicinity of the recent event (Area a), there have rarely been earthquakes of M4.0 or over, but there was an M4.7 earthquake (maximum seismic intensity 4) on January 3, 2011.

For the seismic activity since 1600, in the region around the recent event, there have sometimes been earthquakes of M7.0 or over. Of these, the Niigata Earthquake (M7.5, maximum seismic intensity 5) occurring on June 16, 1964 caused damage with 26 fatalities, 447 injured persons, 1,960 completely-, 6,640 severely-, and 67,825 partially-collapsed houses (Materials for Comprehensive List of Destructive Earthquakes in Japan). In addition, the tsunami was caused and 5.4 m (trace height) observed at Fuya, Sanpoku town, Niigata prefecture.

Japan Meteorological Agency
[Evaluation of Earthquake Offshore Yamagata Prefecture on June 18, 2019 (June 19, 2019)]