On 26/04/2026 20:23 UTC a magnitude 6.1 earthquake was recorded near WNW of Sarabetsu, Japan, along the Pacific Ring of Fire. Hypocentre depth: 81 km. Coordinates: 42.710°, 142.894°.
Event technical data
| Magnitude | M 6.1 |
| Depth | 81 km |
| Coordinates | 42.7102°, 142.8944° |
| Time (UTC) | 2026-04-26 20:23 UTC |
| Location | 24 km WNW of Sarabetsu, Japan |
| Ring of Fire region | 🇯🇵🇳🇿 West Pacific (Japan/Philippines/NZ) |
Tectonic context
Technical analysis: Intermediate-depth intraslab event (Wadati-Benioff zone). West Pacific seismic belt: Japan (Tohoku 2011 M9.1), Philippines, Indonesia (Sumatra 2004 M9.1), New Zealand (Kaikoura 2016 M7.8).
Why it matters for geotechnical engineering in Japan
Japan lies on the same Pacific Ring of Fire. Major earthquakes in Japan (Tohoku 2011), Sumatra 2004, Cascadia (projected) and other segments share similar tectonic mechanics: subduction of an oceanic plate beneath a continental plate, P/S waves travelling thousands of kilometres, and tsunamigenic potential for shallow (<70 km) coastal events.
For local geotechnical design, monitoring global Ring-of-Fire events supports: (1) calibration of seismic attenuation models, (2) liquefaction lessons in comparable saturated sands, (3) international post-seismic construction experience, and (4) site-specific seismic hazard assessment.
Official sources
USGS Earthquake Hazards: global-coverage international source. View USGS event →
EMSC: European-Mediterranean Seismological Centre, global coverage. EMSC portal →
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