Earthquakes / EVENT RECORD
M 4.6 - 131 km SE of Itoman, Japan
USGS · Every measurement below belongs to the selected record.
Around the epicentre
Regional view · markers are locations, not affected areas
Magnitude
M 4.6
Scale: mb
Depth
10 km
operator assigned
Reported by people
Not published
Number of felt reports
USGS review
reviewed
Review does not imply final measurements
What the record tells us
USGS reports a magnitude 4.6 earthquake in 131 km SE of Itoman, Japan, at a depth of 10 km.
Detailed source data captured 2026-09-30 21:59:41 UTC.
Measurements & confidence
- Event time (UTC)
- 2026-09-30 21:11:57.694 UTC
- Source updated (UTC)
- 2026-09-30 21:53:25.040 UTC
- Location
- 25.217°, 128.508°
- Stations used for location
- 40
- Horizontal error
- 8.61 km
- Depth error
- 1.884 km
- Magnitude error
- 0.082
Errors are the source’s reported uncertainty estimates, not guaranteed bounds. A depth marked “operator assigned” was fixed during analysis.
Shaking & impact
- Instrumental intensity
- Not published
- Felt-report intensity
- Not published
- PAGER impact alert
- Not published
No published assessment does not mean no shaking or no impact. A magnitude value alone cannot establish damage or a tsunami warning.
Nearby seismic activity
Within 500 km · M2.5+ · seven days before the event through the latest query, up to seven days after
09-23
0
09-24
0
09-25
1
09-26
0
09-27
0
09-28
0
09-29
0
09-30
0
Query window: 2026-09-23 21:11:57 to 2026-09-30 21:59:41 UTC. This is spatial proximity, not an identified aftershock sequence.
View the USGS catalogue query ↗Magnitude
M 4.6
Scale: mb
Depth
10 km
operator assigned
Reported by people
Not published
Number of felt reports
USGS review
reviewed
Review does not imply final measurements
What the record tells us
USGS reports a magnitude 4.6 earthquake in 131 km SE of Itoman, Japan, at a depth of 10 km.
Detailed source data captured 2026-09-30 21:59:41 UTC.
Measurements & confidence
- Event time (UTC)
- 2026-09-30 21:11:57.694 UTC
- Source updated (UTC)
- 2026-09-30 21:53:25.040 UTC
- Location
- 25.217°, 128.508°
- Stations used for location
- 40
- Horizontal error
- 8.61 km
- Depth error
- 1.884 km
- Magnitude error
- 0.082
Errors are the source’s reported uncertainty estimates, not guaranteed bounds. A depth marked “operator assigned” was fixed during analysis.
Shaking & impact
- Instrumental intensity
- Not published
- Felt-report intensity
- Not published
- PAGER impact alert
- Not published
No published assessment does not mean no shaking or no impact. A magnitude value alone cannot establish damage or a tsunami warning.
Nearby seismic activity
Within 500 km · M2.5+ · seven days before the event through the latest query, up to seven days after
09-23
0
09-24
0
09-25
1
09-26
0
09-27
0
09-28
0
09-29
0
09-30
0
Query window: 2026-09-23 21:11:57 to 2026-09-30 21:59:41 UTC. This is spatial proximity, not an identified aftershock sequence.
View the USGS catalogue query ↗The record as it develops
This timeline begins when our journal started capturing details. It is not a complete USGS revision history.
Captured 2026-09-30 21:59:41 UTC
First detailed capture · M4.6 · 10 km deep · 1 nearby records
Source updated 2026-09-30 21:53:25 UTC
Magnitude is not shaking
Magnitude describes the earthquake’s size. The shaking experienced at a place depends on distance, depth, local ground conditions and the rupture.
Depth needs context
A reported depth describes the location of the earthquake underground. Some solutions use an assigned depth; uncertainty and review status matter.
Nearby does not mean aftershock
Our regional search finds events by distance and time. Establishing an aftershock sequence requires seismological assessment.
This is a source-linked archive. Source measurements and assessments can change. An archived bulletin is not evidence that a warning is currently active.
In the daily journal
30 September 2026 ↗SOURCE ID usgs:us6000tym9