11 October 2000
Headquarters for Earthquake Research Promotion
Earthquake Research Committee

Seismic activity in the area from Miyakejima to Niijima-Kozushima

*The seismic activity in the area from Miyakejima to Niijima-Kozushima, which started at the end of June and was active throughout July and up to the middle of August, has been gradually declining since mid-August. On September 11th there was an M5.3 event 5 km to the west of Toshima, registering a maximum seismic intensity of 5 lower, however activity as a whole has continued to decline since the beginning of September.

*The results of GPS observation of the area show movement, including local crustal movement, has nearly stopped.

*From the above, it can be concluded that the levels of seismic activity and crustal movement have declined.

And so it is believed that the continued seismic activity that began at the end of June has for the most part abated.

*A long-term examination of the Niijima-Kozushima area shows increased seismic activity since the beginning of the 1990s and visible crustal movement.