M 4.9 in Tonga on 21 Dec 2012 01:45 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: 4.9M
Depth: Km
Lat/Lon: -20.7346 , -174.105
Event Date: 21 Dec 2012 01:45 UTC
20 Dec 2012 13:45 Local
Exposed Population:
About 1000 people within 100km
Source: NEIC usc000ee2a
Inserted at: 21 Dec 2012 02:02 UTC

GDACS Score

For more info on GDACS alert score click here.
  Earthquake GDACS score
NEIC 0.5 0.5
usc000ee2a Scaled population (vector) n.a  
  C1 earthquake n.a  
  C2 earthquake n.a  
  Country Vulnerability n.a  
  INFORM_normalised n.a  
Maximum expected impact using different data sources.

Episode Timeline

IDAlertScoreDateMag, DepthMMI*Population**Tsunami risk***Delay (hh:mm)Source
121541 0.5 21 Dec 2012 01:45 4.9M, 30.7km N/A 1 thousand (in 100km) 00:17 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) .

Radius Population
100 km 1000 people
75 km <1000 people
50 km no 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
Niue Niue 2000 people

Critical infrastructure

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

More information

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