Reviewed by USGS23y ago
M2.9 earthquake south of the Aleutian Islands
Thursday, January 22, 2004, 03:15:22 UTC · 49.920°N, 179.247°E
A magnitude 2.9 earthquake struck south of the Aleutian Islands on Thursday, January 22, 2004, 03:15:22 UTC, at a depth of 41.4 km (shallow).
- Magnitude
- 2.9
- Minor · ml
- Depth
- 41 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
338 kg of TNT
That is about 1/44,601 of the Hiroshima bomb. A magnitude 5.0 releases about 1,413 times more energy.
Tectonic setting
69 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
41 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 5 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M3.5 on February 17, 2004. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 3.5Rat Islands, Aleutian Islands, Alaska22y ago · 29 km W of this epicenter
- 2.8south of the Aleutian Islands22y ago · 20 km E of this epicenter
- 3.1Rat Islands, Aleutian Islands, Alaska22y ago · 23 km N of this epicenter
- 3.4south of the Aleutian Islands23y ago · 14 km E of this epicenter
- 3.3south of the Aleutian Islands23y ago · 12 km SW of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 620 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 · 153 km N of this epicenter
- 8.31906 Western Aleutian Islands (Hawadax/Rat Islands) EarthquakeAugust 17, 1906 · 228 km N of this epicenter
- 7.977 km WSW of Adak, AlaskaJune 10, 1996 · 286 km NE of this epicenter
- 7.8Rat Islands, Aleutian Islands, AlaskaNovember 17, 2003 · 143 km N of this epicenter
- 7.6Rat Islands, Aleutian Islands, AlaskaMarch 30, 1965 · 106 km NW of this epicenter
- 7.4265 km WSW of Adak, AlaskaFebruary 4, 1965 · 170 km N of this epicenter
- 7.388 km WSW of Adak, AlaskaJuly 7, 1929 · 274 km NE of this epicenter
- 7.2238 km WSW of Adak, AlaskaMarch 22, 1905 · 150 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 10 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 · 153 km away · intensity VI
Under $1 million damagetsunami
- 1906M8.3
Aleutian Islands: Rat Islands
17 Aug 1906 · 228 km away
- 1905M7.9
Andreanof Islands
14 Feb 1905 · 180 km away
- 1996M7.9
Andreanof Islands
10 Jun 1996 · 286 km away · intensity VI
tsunami
- 2003M7.8
Aleutian Islands: Rat Islands
17 Nov 2003 · 143 km away
tsunami
- 1916M7.7
Aleutian Islands
6 Feb 1916 · 167 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.