Bonin Islands, Japan region
785 km south-south-east of Hamamatsu, Japan
- Date25 Oct 2026
- Origin time02:09:24 UTC
- Depth490 km
- Distance to Armenia8,350–8,470 km
Recorded by CHARNET stations in Armenia
On 25 October 2026 at 02:09 UTC a magnitude 6.5 earthquake occurred beneath the Bonin Islands, south of Japan. Not near the surface, but 490 kilometres deep. Its waves reached Armenia, about 8,400 km away, in less than eleven minutes.
How can rock break so deep, where it is hot and under enormous pressure? Here the Pacific plate dives beneath the Philippine Sea plate and sinks far into the mantle. The slab stays colder than the mantle around it, and it can still produce earthquakes. Events deeper than 300 km are called deep-focus earthquakes.
Vertical component, 0.04–1.5 Hz, about 23 minutes of record, shown 60× faster: blue — P-waves, gold — S-waves. Times after the origin. Arrival marks follow the iasp91 travel-time model for a source 490 km deep and agree with the records.
- 10 min 51 sThe first P-wave reaches Antarashat (ANTS)
- +6 sThe same wave arrives at Byurakan (BRKN) in the west
- 19 min 50 sThe slower S-wave arrives: about 9 minutes after the P-wave
Event parameters: EMSC · Records: CHARNET, IGES