M4.2 earthquake 15 km ESE of It?, Japan
A magnitude 4.2 earthquake struck 15 km ESE of It?, Japan on Thu, Sep 6, 1984, 3:48 AM JST (18:48 UTC), 17 km (11 mi) below the surface.
A larger quake followed: M4.5 7 km S of Katsuura, Japan. This one was a foreshock.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 4.2 (mb), light
- Local time
- UTC
- 1984-09-05 18:48:00 UTC
- Depth
- 17.3 km (10.7 mi), shallow
- Epicenter
- 34.919° N, 139.247° E
- Region
- Japan
- Tsunami flag
- No
- Status
- Reviewed by a seismologist
Did you feel it?
No one has reported feeling this quake to the USGS.
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 1.5 and up: 2 in the 60 days after this one and 2 in the 30 days before it.
After
- 3.914 km SE of It?, Japan · 15357 days ago · 14 km deep · 6 km away
- 4.57 km S of Katsuura, Japan · 15334 days ago · 32 km deep · 98 km away
Before
Earthquakes todayJapan earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event usp000273n. Read Tue, Sep 22, 2026, 12:10 PM UTC.