Reviewed by USGSAlaska23y ago
M3.2 earthquake in Rat Islands, Aleutian Islands, Alaska
Monday, December 22, 2003, 07:38:41 UTC · 50.080°N, 178.940°E
A magnitude 3.2 earthquake struck in Rat Islands, Aleutian Islands, Alaska on Monday, December 22, 2003, 07:38:41 UTC, at a depth of 10.0 km (shallow).
- Magnitude
- 3.2
- Minor · ml
- Depth
- 10 km
- Shallow
- 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
951 kg of TNT
That is about 1/15,825 of the Hiroshima bomb. A magnitude 5.0 releases about 501 times more energy.
Tectonic setting
55 km
from the nearest mapped plate boundary, between the North American and Pacific plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
10 km
Shallow earthquakes (under 70 km) produce the strongest surface shaking for their size, so they are the ones most likely to cause damage near the epicenter.
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 8 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.5 on December 23, 2003. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 3.1Rat Islands, Aleutian Islands, Alaska23y ago · 34 km W of this epicenter
- 3.2Rat Islands, Aleutian Islands, Alaska23y ago · 28 km NW of this epicenter
- 3.6Rat Islands, Aleutian Islands, Alaska23y ago · 34 km N of this epicenter
- 3.4Rat Islands, Aleutian Islands, Alaska23y ago · 21 km NW of this epicenter
- 4.5south of the Aleutian Islands23y ago · 49 km E of this epicenter
- 3.3south of the Aleutian Islands23y ago · 44 km E of this epicenter
- 3.3south of the Aleutian Islands23y ago · 41 km E of this epicenter
- 3.6south of the Aleutian Islands23y ago · 47 km SE of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 633 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.71965 Western Aleutian Islands (Hawadax/Rat Islands) EarthquakeFebruary 4, 1965 · 131 km N of this epicenter
- 8.31906 Western Aleutian Islands (Hawadax/Rat Islands) EarthquakeAugust 17, 1906 · 204 km N of this epicenter
- 7.977 km WSW of Adak, AlaskaJune 10, 1996 · 292 km NE of this epicenter
- 7.8Rat Islands, Aleutian Islands, AlaskaNovember 17, 2003 · 120 km N of this epicenter
- 7.6Rat Islands, Aleutian Islands, AlaskaMarch 30, 1965 · 79 km W of this epicenter
- 7.4265 km WSW of Adak, AlaskaFebruary 4, 1965 · 158 km N of this epicenter
- 7.388 km WSW of Adak, AlaskaJuly 7, 1929 · 280 km NE of this epicenter
- 7.2238 km SSE of Attu Station, AlaskaSeptember 8, 1939 · 299 km W 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:
- 1965M8.7
Aleutian Islands: Rat Islands
4 Feb 1965 · 131 km away · intensity VI
Under $1 million damagetsunami
- 1906M8.3
Aleutian Islands: Rat Islands
17 Aug 1906 · 204 km away
- 1905M7.9
Andreanof Islands
14 Feb 1905 · 192 km away
- 1996M7.9
Andreanof Islands
10 Jun 1996 · 292 km away · intensity VI
tsunami
- 2003M7.8
Aleutian Islands: Rat Islands
17 Nov 2003 · 120 km away
tsunami
- 1916M7.7
Aleutian Islands
6 Feb 1916 · 179 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.