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Mw 5.4 Earthquake, Green alert in Tonga on 20 Apr 2017 22:59 UTC
GDACS Event Report - Earthquake impact

Summary

Population map close up
Population map close up. (Source: JRC)
Interactive map: Open

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

  • Earthquake Magnitude 5.4M, Depth:10km
  • on 20 Apr 2017 22:59 UTC
  • Few people within 100km
  • inserted at 20 Apr 2017 23:18:04

Earthquake event

  • Magnitude: 5.4 M
  • Depth: 10 km (very shallow)
  • Source: NEIC NEIC us10008jeq
  • Location (latitude/longitude): -20.5682, -173.6444
  • Time (UTC): 20 Apr 2017 22:59:22
  • Time (ECT): 21 Apr 2017 00:59:22

Earthquake impact details

The earthquake happened in Tonga , of Tonga (population 98,000) .

Population

Population near epicenter
Radius Population
100 km <1000 people
75 km no 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

Affected Populated Places

See complete places

Critical infrastructure

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

Event time line

For accessing reports of previous advisories, please click on the advisory number in the table below.

event calculation detail

Event calculation detail

Reference Id Level Score Type Date Added Population
100km                      20km
Vulnerability
Score
Max Height(m)
 
 
Episode 1164725
1 realtime 2017-04-21 01:18:12 Few people affected No people affected 1.95 0
  Earthquake 182620
0 realtime 2017-04-21 01:18:11 Few people affected No people affected 1.95 0
 
Close
IDAlert Color Date (UTC)Mag. and depthMax Intensity (mmi*)Pop. within 100 kmTsunami risk (max height)Delay (hh:mm) Source
1164725

Calculation Episode detail

Reference Id Level Score Type Date Added Population
100km                      20km
Vulnerability
Score
Max Height(m)
Episode 1164725
1 realtime 2017-04-21 01:18:12 Few people affected No people affected 1.95 0
  Earthquake 182620
0 realtime 2017-04-21 01:18:11 Few people affected No people affected 1.95 0
Close
20 Apr 2017 22:59 5.4M, 10km N/A Few people affected 00:18 NEIC NEIC

(*) Modified Mercalli Intensity Scale

More information

Data resources

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

About the data

Disclaimer

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