Earthquake with magnitude of Mwp 5.5 on date 18-09-2023 and time 19:33:04 (UTC) in region Near east coast of eastern Honshu, Japan [Sea: Japan]

A magnitude Mwp 5.5 earthquake occured in region: Near east coast of eastern Honshu, Japan [Sea: Japan], on

  • 18-09-2023 19:33:04 (UTC)
  • 18-09-2023 21:33:04 (UTC +02:00) Italian time
  • 19-09-2023 04:33:04 (UTC +09:00) local time in the region of the earthquake (Asia/Tokyo)

and geographic coordinates (lat, lon) 38.3820, 141.9440 at 65 km depth.

The earthquake was located by: Sala Sismica INGV-Roma.

Search earthquakes: Any within 30 km radius

The values of hypocentral coordinates and magnitude may be revised at a later time as more information becomes available.

Municipalities within 20 km from the epicenter

No Italian municipalities within 20 km distance.

Municipalities with at least 50000 inhabitants

No Italian municipalities within 100 km from the epicenter with at least 50000 inhabitants.

Recent and historical seismicity
Seismic hazard
Felt maps
Locations history
Type Magnitude Date and Time (UTC) Latitude Longitude Depth (km) Published time (UTC) Author Location ID
mb 5.4
Mwp 5.5

Mwpd 5.6
38.3818 141.944 65 2023-09-18
Sala Sismica INGV-Roma 121204431
Preferred location and magnitude until now.
Origin information


Field Value
Time (UTC) 2023-09-18 19:33:04
Latitude 38.3818
Longitude 141.9440
Depth (km) 65 (from location)
Evaluation mode of Origin automatic
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV-A
Event type earthquake
Origin ID 121204431


Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 16044402
Semi-minor axis of confidence ellipse (meter) 8401476
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 279
Circular confidence region, given by single value of horizontal uncertainty (meter) 13071300.0
Confidence level of the uncertainty (%) 68


Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 102.661
Number of associated phases, regardless of their use for origin computation 1
Number of defining phases 1
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.776959
Epicentral distance of station closest to the epicenter (degree)
Epicentral distance of station farthest from the epicenter (degree)
Number of stations at which the event was observed 0
Number of stations from which data was used for origin computation 0
Magnitudes information


Field Value
Value 5.6
Uncertainty 0.2
Num. used stations 12
Type of magnitude Mwpd
Reference to an origin 121204431
Agency INGV
Autore Auto added
Time of creation (UTC) 2023-09-18 19:45:27


Field Value
Value 5.5
Uncertainty 0.2
Num. used stations 16
Type of magnitude Mwp
Reference to an origin 121204431
Agency INGV
Autore Auto added
Time of creation (UTC) 2023-09-18 19:45:27


Field Value
Value 5.4
Uncertainty 0.2
Num. used stations 39
Type of magnitude mb
Reference to an origin 121204431
Agency INGV
Autore Auto added
Time of creation (UTC) 2023-09-18 19:45:27
TDMT - Time Domain Moment Tensor
Fault Plane solutions in the area
Type Description Link
QuakeML - small Event, Origin, FocalMechanism Download
QuakeML - full Event, Origin, FocalMechanism, Amplitude, Arrival, Pick, Station Magnitude Download