Earthquakes in Japan — September 2026

48 earthquakes were recorded in Japan during September 2026, an average of 1.6 per day.

48 reached magnitude 4 or above and 8 reached magnitude 5 or above. The average focal depth was 68 km.

The month's largest event in Japan was a magnitude 5.6 earthquake near Yonakuni, Japan on 30 September 2026 at 05:00 UTC. A magnitude 5.6 earthquake radiates roughly 3,788 tons of TNT equivalent in seismic energy.

That is close to the Japan monthly average of 56 events over the period we cover, and down from the 59 recorded the previous month.

77% of events here are shallow (under 70 km), 17% intermediate (70–300 km) and 6% deep-focus (over 300 km). That proportion of deep-focus events is the signature of a subduction zone: only a cold slab descending into the mantle stays brittle enough to rupture at those depths.

By band, the catalogue holds 40 in the magnitude 4 range, 8 in the magnitude 5 range.

Activity peaked on 22 September, when 5 events were recorded.

The month's largest events were M5.6 near Yonakuni, Japan on 30 September at 11 km; M5.1 near Naze, Japan on 20 September at 69 km; M5.1 near Uken, Japan on 22 September at 10 km.

That is 14% below the 56 events Japan averages per month across the 23 months on record.