M 6.4 in Tonga on 23 Dec 2018 23:08 UTC

Hazard models

EQ parameters
Shakemap
Tsunami

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: 6.4M
Depth: 100.17 Km
Lat/Lon: -20.3749 , -175.0925
Event Date: 23 Dec 2018 23:08 UTC
23 Dec 2018 11:08 Local
Exposed Population: Less then 100 people in MMI V
About 81000 people within 100km
Source: NEIC us2000iwvb
Inserted at: 23 Dec 2018 23:27 UTC
INFORM Coping capacity of the alert score
4.6 (Tonga)

GDACS Score

For more info on GDACS alert score click here.
  Earthquake
(Shakemap)		 Tsunami GDACS score
NEIC 0 0 0
us2000iwvb Scaled population (vector) 0 Max wave alert 0m  
  C1 shakemap -0.59 Max wave realtime 0m  
  C2 shakemap 0.53      
  Country Vulnerability 0      
  INFORM_normalised 0.94      
Maximum expected impact using different data sources.

Episode Timeline

IDAlertScoreDateMag, DepthMMI*Population**Tsunami risk***Delay (hh:mm)Source
1242337 0 23 Dec 2018 23:08 6.5M, 105.9km N/A 90 thousand (in 100km) 0m (at 00:00) 00:08 PTWC
1242341 0 23 Dec 2018 23:08 6.5M, 100km N/A 90 thousand (in 100km) 0m (at 00:00) 00:10 NTWC    
1242344 0 23 Dec 2018 23:08 6.4M, 100.17km 4.89 N/A (in MMI>=VII) 0m (at 00:00) 00:18 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.

Exposed population

The earthquake happened in Tonga , of Tonga (population 98,000) . The nearest places are and Nuku'alofa.

Radius Population
100 km 82000 people
75 km 1700 people
50 km <1000 people
20 km no people
10 km no people
5 km no people
2 km no people

Affected Provinces

Region Province Country Population
Tonga Tonga 98000 people

Affected populated places

Name Region Province Country City class Population Distance
Nuku'alofa Tonga Capital 24000 people 85 km

see full list

Critical infrastructure

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

Airports

Name IATA Code Elevation (m) Usage Runway type IFR Runway Length (ft) Distance
Fua'amotu International TBU 38 Civ. Paved Yes 8700 96 km

Ports

Name LOCODE Country Distance
Nuku'alofa TOTBU Tonga 85 km
Pangai TOPAN Tonga 100 km

More information

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