M 7.1 in New Caledonia on 20 May 2023 01:51 UTC

Event summary

This earthquake is expected to have a low humanitarian impact based on the magnitude and the affected population and their vulnerability.

Earthquake Magnitude: 7.1M
Depth: 35.981 Km
Lat/Lon: -23.0622 , 170.4562
Event Date: 20 May 2023 01:51 UTC
20 May 2023 12:51 Local
Exposed Population: Few people affected in MMI -
Source: NEIC us6000kdce
Inserted at: 20 May 2023 02:11 UTC
INFORM Coping capacity of the alert score: 1.1 (New Caledonia)


For more info on GDACS alert score click here.
(Rapid Impact)
Tsunami GDACS score
NEIC 0 0.1 0.1
us6000kdce Scaled population (raster) 0 Max wave alert 0.11m  
  C1 rapid impact 0 Max wave realtime 0.14m  
  C2 rapid impact 0      
  Country Vulnerability 0      
  INFORM_normalised 0      
Maximum expected impact using different data sources.

The green area correspond to areas affected by strong shaking (MMI VI or higher) according to the simulation.

Episode Timeline

IDAlertScoreDateMag, DepthMMI*Population**Tsunami risk***Delay (hh:mm)Source
1506560 0 20 May 2023 01:51 7.4M, 44.7km 5.17 N/A (in MMI>=VII) 0.2m (at 00:54) 00:08 PTWC
1506561 0 20 May 2023 01:51 7.4M, 45km 5.14 N/A (in MMI>=VII) 0.2m (at 01:14) 00:09 NTWC
1506563 0 20 May 2023 01:51 7.1M, 35.981km 4.98 N/A (in MMI>=VII) 0.1m (at 00:52) 00:20 NEIC
The episode that generated the alert; the next major evaluations beyond 12 hours will not trigger additional alerts.
The episode that has the last updated information.
* The max MMI detected for sources having shakemaps;
** The population detected in MMI>=7 for episode with shakemap or in a 100km radius;
*** The tsunami max height.

Rapid Impact

The results presented below are calculated with the ShakeMap open source software (USGS) using only earthquake hypocenter information to provide a rapid estimation of the ground motion and shaking intensity without taking into account any instrumental observations or earthquake source scaling laws.

Exposed population

The earthquake happened in unknowed a zone. The alertlevel for this event is GREEN

Intensity Population
<1000 people

Affected Provinces

Critical infrastructure

Airports, ports, nuclear plants and hydrodams at risk, if affected, are listed below.


Intensity Name LOCODE Country Distance
Matthew Island New Caledonia 121 km

More information

For a full list of available products related to this event, please refer to the GDACS Resources page.