Reviewed by USGSTonga22y ago
M4.2 earthquake 293 km W of Haveluloto, Tonga
Friday, December 24, 2004, 21:00:20 UTC · 20.861°S, 178.022°W
A magnitude 4.2 earthquake struck 293 km W of Haveluloto, Tonga on Friday, December 24, 2004, 21:00:20 UTC, at a depth of 418.3 km (deep).
- Magnitude
- 4.2
- Light · mb
- Depth
- 418 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 earthquake
In context
How big was it, and why here?
Energy released
30 tons of TNT
That is about 1/500 of the Hiroshima bomb. A magnitude 5.0 releases about 16 times more energy.
Tectonic setting
178 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
418 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 has not published any M2.5+ earthquake within 50 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 1,119 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.8159 km W of Pangai, TongaDecember 14, 1950 · 258 km NE of this epicenter
- 7.8Fiji regionJanuary 1, 1919 · 172 km N of this epicenter
- 7.8192 km WSW of Haveluloto, TongaOctober 14, 1997 · 189 km SE of this epicenter
- 7.7Fiji regionAugust 19, 2002 · 180 km SW of this epicenter
- 7.5262 km WNW of Haveluloto, TongaMay 21, 1962 · 104 km NE of this epicenter
- 7.4Fiji regionSeptember 28, 1957 · 49 km NW of this epicenter
- 7.4Fiji regionAugust 5, 1996 · 35 km NW of this epicenter
- 7.3227 km WNW of Haveluloto, TongaApril 16, 1937 · 79 km E 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:
- 1937M8.1
Fiji Islands
16 Apr 1937 · 128 km away
- 1919M7.8
Fiji Islands
1 Jan 1919 · 172 km away
tsunami
- 1950M7.7
Tonga Islands
14 Dec 1950 · 260 km away · intensity VI
- 1997M7.7
Tonga Islands
14 Oct 1997 · 189 km away
tsunami
- 2002M7.7
Fiji Islands
19 Aug 2002 · 180 km away
- 1957M7.5
Fiji Islands
28 Sep 1957 · 71 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.