Seismic activity in the sea near Niijima, Kozushima and Miyakejima

Since the start of volcanic activity on Miyakejima on 26 June, there has been continuing seismic activity in the area from Miyakejima to Niijima-Kozushima, with 238 events of M4 or higher recorded in the period from the start of the activity to 10 July.
On 29 June, there was an M5.2 event near Kozushima, which registered a seismic intensity of 5 lower on the island. On 1 July, there was an M6.4 event in the sea 5 km east of Kozushima, which registered a seismic intensity of 6 lower on Kozushima and 5 lower on Niijima. Then on 9 July, there was an M6.1 event 2 km northeast of the 1 July event, which registered a seismic intensity of 6 lower on Kozushima and 4 on Niijima.
It is thought that M5.1 earthquake (marked by the arrow) that occurred at 6:41 p.m. on 8 July was associated with the collapse of the summit of Mt.Oyama on Miyakejima.

Japan Meteorological Agency

Seismic Activity in Japan June 2000