Reviewed by USGSAlaska27y ago
M2.8 earthquake 45 km N of Larsen Bay, Alaska
Friday, December 24, 1999, 06:41:23 UTC · 57.944°N, 154.018°W
A magnitude 2.8 earthquake struck 45 km N of Larsen Bay, Alaska on Friday, December 24, 1999, 06:41:23 UTC, at a depth of 48.2 km (shallow).
- Magnitude
- 2.8
- Minor · ml
- Depth
- 48 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 earthquake
In context
How big was it, and why here?
Energy released
239 kg of TNT
That is about 1/63,000 of the Hiroshima bomb. A magnitude 5.0 releases about 1,995 times more energy.
Tectonic setting
234 km
from the nearest mapped plate boundary, between the North American and Pacific plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
48 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 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 327 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.9Kodiak Island region, AlaskaOctober 9, 1900 · 189 km E of this epicenter
- 7.14 km ENE of Karluk, AlaskaNovember 7, 1912 · 45 km SW of this epicenter
- 7.0153 km SE of Halibut Cove, AlaskaDecember 23, 1906 · 275 km E of this epicenter
- 7.0113 km ESE of Chignik, AlaskaMay 4, 1923 · 288 km SW of this epicenter
- 7.026 km SSE of Karluk, AlaskaDecember 6, 1999 · 70 km S of this epicenter
- 6.9143 km ESE of Chignik, AlaskaFebruary 13, 1951 · 275 km SW of this epicenter
- 6.9171 km SW of Akhiok, AlaskaFebruary 6, 1964 · 271 km SW 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:
- 1900M8.3
Kodiak Island
9 Oct 1900 · 100 km away · intensity VIII
Limited damage (under $1M)
- 1788M8.0
Unga Island
21 Jul 1788 · 121 km away · intensity VII
Limited damage (under $1M)tsunami
- 1970M6.0
Andreanof Islands
11 Mar 1970 · 50 km away · intensity V
Limited damage (under $1M)tsunami
- 1792
Kodiak Island
1792 · 160 km away · intensity VII
Limited damage (under $1M)tsunami
- 1906M7.6
Aleutian Islands
23 Dec 1906 · 122 km away
- 1912M7.5
Alaska Peninsula
7 Nov 1912 · 76 km away · intensity V
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.