Home > Publications/Periodicals > The Seismological Bulletin of Japan > Notice > 13/03/2018


In the case of high seismic activity, such as during aftershocks immediately following a large earthquake, or during an earthquake swarm, the JMA may change the event processing threshold due to the large number of events. We had changed the threshold as below, but we finished the analysis and added the data on 13, May 2018.

Time duration Magnitude threshold Area
21:00 JST, 14 Apr. 2016 – 23:59 JST, 24 July 2016 2.0 Blue rectangle in the below figure

The number of the earthquakes, the distribution map and the magnitude frequency diagram of the additional data are as below.

determination flag
K k S s A a Total
The number of
the earthquakes
172 15 0 0 40595 11260 52042