Reviewed by USGSFiji8y ago
M4.6 earthquake 217 km E of Levuka, Fiji
Thursday, October 4, 2018, 19:37:58 UTC · 17.694°S, 178.669°W
A magnitude 4.6 earthquake struck 217 km E of Levuka, Fiji on Thursday, October 4, 2018, 19:37:58 UTC, at a depth of 550.2 km (deep). It is the strongest earthquake within 300 km since an M5.5 on October 4, 2018.
- Magnitude
- 4.6
- Light · mb
- Depth
- 550 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
120 tons of TNT
That is about 1/126 of the Hiroshima bomb. A magnitude 5.0 releases about 4 times more energy.
Tectonic setting
195 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
550 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 9 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.5 on October 15, 2018. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 4.4208 km E of Levuka, Fiji8y ago · 24 km S of this epicenter
- 4.4216 km E of Levuka, Fiji8y ago · 4 km S of this epicenter
- 4.2189 km E of Levuka, Fiji8y ago · 50 km SW of this epicenter
- 4.3234 km E of Levuka, Fiji8y ago · 35 km SE of this epicenter
- 4.3249 km E of Levuka, Fiji8y ago · 48 km SE of this epicenter
- 4.3218 km E of Levuka, Fiji8y ago · 25 km S of this epicenter
- 4.1191 km ENE of Levuka, Fiji8y ago · 49 km NW of this epicenter
- 4.5226 km E of Levuka, Fiji8y ago · 34 km SE of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 1,259 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 · 72 km SE of this epicenter
- 7.945 km S of Levuka, FijiSeptember 6, 2018 · 227 km SW of this epicenter
- 7.8Fiji regionJanuary 1, 1919 · 191 km S of this epicenter
- 7.6178 km E of Levuka, FijiFebruary 22, 1909 · 65 km SW of this epicenter
- 7.6144 km SSW of Leava, Wallis and FutunaMay 23, 1956 · 252 km N of this epicenter
- 7.6240 km E of Levuka, FijiMarch 9, 1994 · 47 km SE of this epicenter
- 7.5262 km WNW of Haveluloto, TongaMay 21, 1962 · 295 km SE of this epicenter
- 7.4227 km E of Levuka, FijiAugust 21, 1910 · 19 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 8 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 · 202 km away · intensity VIII
Moderate damage ($1–5M)
- 1979M6.9
Fiji Islands
16 Nov 1979 · 174 km away
Moderate damage ($1–5M)tsunami
- 1932M6.4
Koro,Mudu,Suvasavu
8 Mar 1932 · 176 km away · intensity VII
Moderate damage ($1–5M)
- 2018M8.2
Fiji Islands
19 Aug 2018 · 72 km away · intensity V
tsunami
- 2018M7.9
Fiji Islands
6 Sep 2018 · 227 km away · intensity VII
- 1909M7.8
Fiji Islands
22 Feb 1909 · 49 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.