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.

ShakeMap is a product of the USGS Earthquake Hazards Program in conjunction with the regional seismic networks. ShakeMaps provide near-real-time maps of ground motion and shaking intensity following significant earthquakes.


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 36,817) . The alertlevel for this event is GREEN

Intensity Population
<1000 people
no people


Shakemaps Timeline

AlertShake id #ScoreepisodeidLat/LonMagnitudeDepthMax MMIDate shake (UTC)Delay (hh:mm) 
1 0 1242344 -20.375/-175.092 6.4 100.17 4.89 23 Dec 2018 23:28 00:19 (new episode)
2 0 1242344 -20.375/-175.092 6.4 100.17 4.89 24 Dec 2018 01:12 02:03 (upd of #1)

Affected Provinces

Intensity Region Province Country Population
Tonga Tonga 37000 people
Tonga Tonga 14000 people

Affected populated places. Areas of interest

Intensity Name Region Province Country City class Population Distance
Kolonga Tonga Village - 85 km
Nuku'alofa Tonga Capital 24000 people 85 km
Foui Tonga Village - 86 km
Niutoua Tonga Village - 86 km
Nukunuku Tonga Village - 87 km
Pea Tonga Village - 89 km
Mua Tonga Village - 90 km
Houma Tonga Village - 90 km
Fatumu Tonga Village - 93 km
Fuaamotu Tonga Village - 98 km
Pangai Tonga Village 1700 people 99 km
Ohonua Tonga Village 1200 people 108 km
Neiafu Tonga Village 4300 people 224 km

see full list


Critical infrastructure

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

Airports

Intensity Name IATA Code Elevation (m) Usage Runway type IFR Runway Length (ft) Distance
Fua'amotu International TBU 38 Civ. Paved Yes 8700 96 km
Haapai HPA 12 Civ. Unpaved Yes 3900 103 km
Eua Kaufana EUA unknown 0 112 km
Vavau International VAV 72 Civ. Unpaved Yes 5500 231 km
Ono-I-Lau ONU unknown 0 378 km

Ports

Intensity Name LOCODE Country Distance
Nuku'alofa TOTBU Tonga 85 km
Pangai TOPAN Tonga 100 km
Eua Island Tonga 111 km
Neiafu TONEI Tonga 224 km
Ata Island Tonga 245 km

More information

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