Reviewed by USGS40y ago
M7.1 earthquake south of the Fiji Islands
Monday, June 16, 1986, 10:48:25 UTC · 22.037°S, 178.925°W
A magnitude 7.1 earthquake struck south of the Fiji Islands on Monday, June 16, 1986, 10:48:25 UTC, at a depth of 547.0 km (deep). It is the strongest earthquake within 300 km since an M7.2 on February 10, 1969.
- Magnitude
- 7.1
- Major · mw
- Depth
- 547 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: 200 km aftershock search area
In context
How big was it, and why here?
Energy released
674 kilotons of TNT
That is about 45 times the Hiroshima bomb. It released about 1,413 times the energy of a magnitude 5.0.
Tectonic setting
232 km
from the nearest mapped plate boundary, between the Tonga and Australian plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: deep
547 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 200 km
USGS lists 5 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M5.8 on July 2, 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 606 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.5262 km WNW of Haveluloto, TongaMay 21, 1962 · 265 km NE of this epicenter
- 7.4Fiji regionSeptember 28, 1957 · 177 km N of this epicenter
- 7.3227 km WNW of Haveluloto, TongaApril 16, 1937 · 231 km NE of this epicenter
- 7.3Fiji regionMay 25, 1944 · 74 km NW of this epicenter
- 7.2Fiji regionOctober 9, 1967 · 99 km N of this epicenter
- 7.2south of the Fiji IslandsFebruary 10, 1969 · 247 km W of this epicenter
- 7.2241 km WNW of Houma, TongaAugust 21, 1911 · 284 km NE of this epicenter
- 7.2280 km WNW of Houma, TongaDecember 14, 1910 · 219 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 2 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1937M8.1
Fiji Islands
16 Apr 1937 · 208 km away
- 1957M7.5
Fiji Islands
28 Sep 1957 · 187 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.