Reviewed by USGS8y ago
M4.3 earthquake in Fiji region
Monday, October 1, 2018, 09:06:58 UTC · 17.629°S, 178.976°W
A magnitude 4.3 earthquake struck in Fiji region on Monday, October 1, 2018, 09:06:58 UTC, at a depth of 532.2 km (deep).
- Magnitude
- 4.3
- Light · mb
- Depth
- 532 km
- Deep
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 50 km aftershock search area
In context
How big was it, and why here?
Energy released
43 tons of TNT
That is about 1/354 of the Hiroshima bomb. A magnitude 5.0 releases about 11 times more energy.
Tectonic setting
211 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
532 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
No “Did You Feel It?” reports have been published for this event yet. If you felt it, you can add your report on the USGS website.
I felt it — report to USGS ↗USGS PAGER estimate
Who was exposed to shaking
USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No PAGER estimate is available for this event.
After the main event
Aftershocks within 50 km
USGS lists 4 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.6 on October 4, 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 1,198 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.22018 Fiji EarthquakeAugust 19, 2018 · 102 km SE of this epicenter
- 7.945 km S of Levuka, FijiSeptember 6, 2018 · 200 km SW of this epicenter
- 7.8Fiji regionJanuary 1, 1919 · 210 km SE of this epicenter
- 7.6178 km E of Levuka, FijiFebruary 22, 1909 · 63 km S of this epicenter
- 7.6144 km SSW of Leava, Wallis and FutunaMay 23, 1956 · 245 km N of this epicenter
- 7.6240 km E of Levuka, FijiMarch 9, 1994 · 75 km SE of this epicenter
- 7.4227 km E of Levuka, FijiAugust 21, 1910 · 50 km SE of this epicenter
- 7.377 km ENE of Ba, FijiNovember 9, 2009 · 289 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 12 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1919M6.9
Rabi,Tunuloa Mission,Suvasavu
3 Oct 1919 · 175 km away · intensity VIII
Moderate damage ($1–5M)
- 1979M6.9
Fiji Islands
16 Nov 1979 · 144 km away
Moderate damage ($1–5M)tsunami
- 1932M6.4
Koro,Mudu,Suvasavu
8 Mar 1932 · 149 km away · intensity VII
Moderate damage ($1–5M)
- 1884
Macuata
Jan 1884 · 281 km away · intensity VII
Limited damage (under $1M)tsunami
- 2018M8.2
Fiji Islands
19 Aug 2018 · 102 km away · intensity V
tsunami
- 2018M7.9
Fiji Islands
6 Sep 2018 · 200 km away · intensity VII
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.