Reviewed by USGS24y ago
M5.0 earthquake in Fiji region
Tuesday, January 21, 2003, 21:57:22 UTC · 20.543°S, 178.354°W
A magnitude 5.0 earthquake struck in Fiji region on Tuesday, January 21, 2003, 21:57:22 UTC, at a depth of 530.1 km (deep). It is the strongest earthquake within 300 km since an M5.6 on January 20, 2003.
- Magnitude
- 5.0
- Moderate · mb
- Depth
- 530 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: 75 km aftershock search area
In context
How big was it, and why here?
Energy released
477 tons of TNT
That is about 1/32 of the Hiroshima bomb. Each whole step in magnitude is about 32 times more energy.
Tectonic setting
221 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
530 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 75 km
USGS lists 7 M2.5+ earthquakes within 75 km in the following 30 days; the largest was M4.7 on February 14, 2003. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 4.3287 km WNW of Haveluloto, Tonga23y ago · 57 km E of this epicenter
- 4.7Fiji region23y ago · 54 km N of this epicenter
- 4.6Fiji region23y ago · 25 km NE of this epicenter
- 4.6Fiji region23y ago · 7 km E of this epicenter
- 4.3Fiji region23y ago · 54 km W of this epicenter
- 4.4Fiji region24y ago · 67 km SW of this epicenter
- 4.4Fiji region24y ago · 67 km SW of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 1,185 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 · 275 km E of this epicenter
- 7.8Fiji regionJanuary 1, 1919 · 139 km N of this epicenter
- 7.8192 km WSW of Haveluloto, TongaOctober 14, 1997 · 238 km SE of this epicenter
- 7.7Fiji regionAugust 19, 2002 · 176 km SW of this epicenter
- 7.6178 km E of Levuka, FijiFebruary 22, 1909 · 270 km N of this epicenter
- 7.6240 km E of Levuka, FijiMarch 9, 1994 · 279 km N of this epicenter
- 7.5262 km WNW of Haveluloto, TongaMay 21, 1962 · 106 km NE of this epicenter
- 7.4Fiji regionSeptember 28, 1957 · 1 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 9 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1937M8.1
Fiji Islands
16 Apr 1937 · 176 km away
- 1909M7.8
Fiji Islands
22 Feb 1909 · 291 km away
- 1919M7.8
Fiji Islands
1 Jan 1919 · 139 km away
tsunami
- 1950M7.7
Tonga Islands
14 Dec 1950 · 272 km away · intensity VI
- 1997M7.7
Tonga Islands
14 Oct 1997 · 238 km away
tsunami
- 2002M7.7
Fiji Islands
19 Aug 2002 · 176 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.