Reviewed by USGS52y ago
M6.2 earthquake south of the Fiji Islands
Saturday, February 22, 1975, 22:04:37 UTC · 24.886°S, 179.061°W
A magnitude 6.2 earthquake struck south of the Fiji Islands on Saturday, February 22, 1975, 22:04:37 UTC, at a depth of 375.0 km (deep). It is the strongest earthquake within 300 km since an M6.4 on December 28, 1973.
- Magnitude
- 6.2
- Strong · mb
- Depth
- 375 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: 100 km aftershock search area
In context
How big was it, and why here?
Energy released
30 kilotons of TNT
That is about 2 times the Hiroshima bomb. It released about 63 times the energy of a magnitude 5.0.
Tectonic setting
146 km
from the nearest mapped plate boundary, between the Kermadec and Australian plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: deep
375 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 100 km
USGS lists 1 M2.5+ earthquake within 100 km in the following 30 days; the largest was M4.7 on February 23, 1975. 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 91 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.6south of the Fiji IslandsDecember 18, 1963 · 224 km E of this epicenter
- 7.3south of the Fiji IslandsJanuary 20, 1970 · 216 km SE of this epicenter
- 7.3south of the Fiji IslandsMarch 30, 1972 · 163 km SW of this epicenter
- 7.2south of the Fiji IslandsNovember 24, 1960 · 285 km E of this epicenter
- 6.8south of the Fiji IslandsJuly 4, 1963 · 212 km SE of this epicenter
- 6.7south of the Fiji IslandsSeptember 8, 1920 · 279 km E of this epicenter
- 6.7south of the Fiji IslandsAugust 12, 1967 · 176 km E of this epicenter
- 6.6south of the Fiji IslandsNovember 23, 1960 · 280 km E 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:
- 1932M7.9
Kermadec Islands
26 May 1932 · 188 km away
- 1963M7.5
Tonga Trench
18 Dec 1963 · 249 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.