Reviewed by USGSAlaska26y ago
M5.4 earthquake 27 km SW of Larsen Bay, Alaska
Wednesday, March 8, 2000, 14:20:57 UTC · 57.341°N, 154.252°W
A magnitude 5.4 earthquake struck 27 km SW of Larsen Bay, Alaska on Wednesday, March 8, 2000, 14:20:57 UTC, at a depth of 39.5 km (shallow). It is the strongest earthquake within 300 km since an M6.4 on December 7, 1999.
- Magnitude
- 5.4
- Moderate · mw
- Depth
- 40 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: 75 km aftershock search area
In context
How big was it, and why here?
Energy released
2 kilotons of TNT
That is about 1/8 of the Hiroshima bomb. It released about 4 times the energy of a magnitude 5.0.
Tectonic setting
187 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
40 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 75 km
USGS lists 1 M2.5+ earthquake within 75 km in the following 30 days; the largest was M2.8 on March 21, 2000. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 313 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 · 195 km E of this epicenter
- 7.14 km ENE of Karluk, AlaskaNovember 7, 1912 · 29 km N of this epicenter
- 7.0113 km ESE of Chignik, AlaskaMay 4, 1923 · 227 km SW of this epicenter
- 7.026 km SSE of Karluk, AlaskaDecember 6, 1999 · 6 km W of this epicenter
- 7.0164 km SE of Chignik, AlaskaSeptember 4, 1989 · 262 km SW of this epicenter
- 6.9143 km ESE of Chignik, AlaskaFebruary 13, 1951 · 211 km SW of this epicenter
- 6.9171 km SW of Akhiok, AlaskaFebruary 6, 1964 · 205 km SW 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:
- 1900M8.3
Kodiak Island
9 Oct 1900 · 54 km away · intensity VIII
Limited damage (under $1M)
- 1788M8.0
Unga Island
21 Jul 1788 · 84 km away · intensity VII
Limited damage (under $1M)tsunami
- 1970M6.0
Andreanof Islands
11 Mar 1970 · 27 km away · intensity V
Limited damage (under $1M)tsunami
- 1792
Kodiak Island
1792 · 141 km away · intensity VII
Limited damage (under $1M)tsunami
- 1906M7.6
Aleutian Islands
23 Dec 1906 · 59 km away
- 1912M7.5
Alaska Peninsula
7 Nov 1912 · 48 km away · intensity V
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.