Magnitude8.2

Reviewed by USGS8y ago

M8.2 earthquake 2018 Fiji Earthquake

Sunday, August 19, 2018, 00:19:40 UTC · 18.113°S, 178.153°W

A magnitude 8.2 earthquake struck 2018 Fiji Earthquake on Sunday, August 19, 2018, 00:19:40 UTC, at a depth of 600.0 km (deep). USGS received 36 “Did You Feel It?” reports, with a maximum reported intensity of V (moderate). The USGS PAGER alert is green: low likelihood of casualties and damage. No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.

Tsunami flagUSGS sets this flag for large events in oceanic regions so tsunami warning centers review them. It does not by itself mean a tsunami occurred. Check tsunami.gov and local authorities for official messages.

Magnitude
8.2
Great · mww
Depth
600 km
Deep
Felt reports
36
Max intensity V
Est. shaking
IV
Light (ShakeMap)
PAGER alert
Green
Impact estimate
Tsunami
Flag
Check tsunami.gov

Outlined circle: this earthquakeDashed circle: 400 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

30 megatons of TNT

That is about 1,998 times the Hiroshima bomb. It released about 63,096 times the energy of a magnitude 5.0.

Tectonic setting

180 km

from the nearest mapped plate boundary, between the Niuafo'ou and Australian plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.

Depth: deep

600 km

Deep earthquakes (over 300 km) happen deep inside subducting plates. They rarely cause damage, but can be felt faintly over very large distances.

Did You Feel It?

Where it was felt

Reports sent by people to USGS, grouped by place (most reports first). Intensity uses the Modified Mercalli scale (I–X): what people felt, not the magnitude.

PlaceIntensityReportsDistance
Nadi, Western, Fiji IslandsV · Moderate4762 km
Suva, Central, Fiji IslandsV · Moderate3700 km
Nausori, Central, Fiji IslandsV · Moderate2695 km
Honiara, Guadalcanal, Solomon IslandsII · Weak22628 km
Levuka, Eastern, Fiji IslandsV · Moderate1682 km
Haveloloto, Tongatapu, TongaIV · Light1753 km
Vaiaku, Funafuti, TuvaluIII · Weak11252 km
Vila, Shefa, VanuatuIII · Weak11555 km
Nouméa, Sud, New CaledoniaIII · Weak11779 km
Tofoa-Koloua, Tongatapu, TongaIII · Weak1754 km
Talimatau, North West Upolu, SamoaIII · Weak11023 km
Siupapa, Rest of Upolu, SamoaII · Weak11039 km
I felt it — report to USGS ↗

USGS PAGER estimate

Who was exposed to shaking

Modelled from the ShakeMap and population data. Alert level green: low likelihood of casualties and damage.

IV · Light shaking
966,000 people
III · Weak shaking
66,000 people

After the main event

Aftershocks within 400 km

USGS lists 431 M2.5+ earthquakes within 400 km in the following 30 days; the largest was M7.9 on September 6, 2018. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 1,448 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 10 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:

  1. 1919M6.9

    Rabi,Tunuloa Mission,Suvasavu

    3 Oct 1919 · 273 km away · intensity VIII

    Moderate damage ($1–5M)

  2. 1979M6.9

    Fiji Islands

    16 Nov 1979 · 246 km away

    Moderate damage ($1–5M)tsunami

  3. 1932M6.4

    Koro,Mudu,Suvasavu

    8 Mar 1932 · 221 km away · intensity VII

    Moderate damage ($1–5M)

  4. 2018M8.2

    Fiji Islands

    19 Aug 2018 · 0 km away · intensity V

    tsunami

  5. 2018M7.9

    Fiji Islands

    6 Sep 2018 · 267 km away · intensity VII

  6. 1909M7.8

    Fiji Islands

    22 Feb 1909 · 90 km away

NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.

Nearby trackers

Closest city pages