A magnitude 6.5 earthquake struck the Bonin Islands region of Japan at 02:09 UTC on Sunday, October 25, at a depth of 492.4 km, the US Geological Survey (USGS) said in its reviewed solution for event us6000u4r9. The epicentre was at 27.795°N, 139.618°E, beneath the Pacific southeast of Honshu, and the USGS issued a green PAGER alert, indicating a low likelihood of casualties and damage.

Source: USGS event us6000u4r9 via EarthquakeToday, Oct 25, 2026

The European-Mediterranean Seismological Centre (EMSC) initially measured the same event at magnitude 6.3, Reuters reported. Early readings from different agencies often differ slightly; the USGS reviewed figure, based on 124 reporting stations, is magnitude 6.5 at 492.4 km depth.

Source: Reuters via Inshorts (EMSC), Oct 25, 2026

The defining feature of this quake is its depth. At almost 500 km down — in what seismologists call the deep-focus zone — the energy was heavily damped long before it could shake the surface: the USGS recorded no felt reports and put the maximum estimated shaking intensity at zero, monitoring based on USGS data noted. The Bonin (Ogasawara) Islands are remote and sparsely populated, and no casualties or damage had been reported in the agency data available when this story was published.

Source: Watchers monitoring of USGS data, Oct 25, 2026

Fifteen minutes later, at 02:24 UTC, a separate magnitude 6.2 earthquake struck near Port-Olry in Vanuatu, in the same broad Pacific seismic system. Read: Magnitude 6.2 earthquake near Port-Olry, Vanuatu

The Bonin Islands region lies along the Izu–Bonin–Mariana arc, where the Pacific Plate subducts beneath the Philippine Sea Plate — a system known for deep and powerful seismic activity, monitoring based on USGS data noted. Deep-focus quakes of this size are closely watched by seismologists but rarely cause surface destruction; the USGS figures may still be revised as analysis continues.

Source: Watchers monitoring of USGS data, Oct 25, 2026