Reviewed by USGSFiji40y ago
M4.8 earthquake 227 km SSE of Suva, Fiji
Wednesday, May 28, 1986, 07:31:25 UTC · 20.151°S, 178.890°E
A magnitude 4.8 earthquake struck 227 km SSE of Suva, Fiji on Wednesday, May 28, 1986, 07:31:25 UTC, at a depth of 555.7 km (deep). It is the strongest earthquake within 300 km since an M5.5 on May 26, 1986.
- Magnitude
- 4.8
- Light · mb
- Depth
- 556 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
239 tons of TNT
That is about 1/63 of the Hiroshima bomb. A magnitude 5.0 releases about 2 times more energy.
Tectonic setting
311 km
from the nearest mapped plate boundary, between the Australian and Conway Reef plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: deep
556 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 M5.2 on June 5, 1986. 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 291 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.4Fiji regionSeptember 28, 1957 · 291 km E of this epicenter
- 7.3Fiji regionMay 25, 1944 · 235 km SE of this epicenter
- 7.2Fiji regionOctober 9, 1967 · 231 km SE of this epicenter
- 7.2south of the Fiji IslandsFebruary 10, 1969 · 294 km S of this epicenter
- 7.1Fiji regionFebruary 25, 1915 · 252 km SE of this epicenter
- 7.1Fiji regionJanuary 27, 1948 · 267 km E of this epicenter
- 7.1Fiji regionMay 4, 1924 · 275 km SE of this epicenter
- 7.1230 km S of Suva, FijiMay 26, 1986 · 5 km SW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 5 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 48 recorded deaths. The most severe:
- 1840
Kadavu
1840 · 158 km away · intensity VIII
40 deathsLimited damage (under $1M)
- 1953M6.4
Fiji Islands
14 Sep 1953 · 218 km away
8 deathsLimited damage (under $1M)tsunami
- 1932M6.4
Koro,Mudu,Suvasavu
8 Mar 1932 · 235 km away · intensity VII
Moderate damage ($1–5M)
- 1957M7.5
Fiji Islands
28 Sep 1957 · 274 km away
- 1975M4.9
Fiji Islands
16 Dec 1975 · 170 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.