Kanto-Chubu Region

a) On July 21st, there was an M6.0 event (maximum seismic intensity 5 lower) occurring in conjunction with the subduction of the Pacific Plate in the sea off the coast of Ibaraki Prefecture.
b) On July 6th, there wan an M5.0 event in the sea off the east coast of the Kanto region.
c) On July 21st, there was an M5.6 event in the sea to the east of Chiba Prefecture.
d) There was intense seismic activity in the area from Miyakejima to Niijima-Kozushima, with an M6.4 event (maximum seismic intensity 6 lower) in the sea east of Kozushima on July 1st, an M6.1 event (maximum seismic intensity 6 lower) on July 9th, an M6.3 event (maximum seismic intensity 6 lower) in the sea west of Niijima on July 15th, and an M6.4 event (maximum seismic intensity 6 lower) in the sea southwest of Miyakejima on July 30th.

In addition, outside the area being discussed, there was a deep M7.3 event (at a depth of 430 km) in the sea near Torishima.

Note: Within square brackets ([ ]) is the epicenter place name used by the Meteorological Agency in its information releases.

Note:
M=magnitude
N: total number of events in the figure
depth=depth of hypocenter
UND=Earthquakes of less than M1.0 and earthquakes whose magnitude was not recorded.
The key to the symbols shows on the left the size of an earthquake and on the right the depth of the hypocenter.

Japan Meteorological Agency,Science and Technology Agency