Reviewed by USGSAlaska121y ago
M7.0 earthquake 153 km SE of Halibut Cove, Alaska
Sunday, December 23, 1906, 17:21:32 UTC · 58.556°N, 149.472°W
A magnitude 7.0 earthquake struck 153 km SE of Halibut Cove, Alaska on Sunday, December 23, 1906, 17:21:32 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.9 on October 9, 1900.
- Magnitude
- 7.0
- Major · mw
- Depth
- 15 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
529 kilotons of TNT
That is about 35 times the Hiroshima bomb. It released about 1,109 times the energy of a magnitude 5.0.
Tectonic setting
141 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
15 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 200 km
USGS has not published any M2.5+ earthquake within 200 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 1 M5.0+ earthquake within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 5 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1900M8.3
Kodiak Island
9 Oct 1900 · 288 km away · intensity VIII
Limited damage (under $1M)
- 1788M8.0
Unga Island
21 Jul 1788 · 271 km away · intensity VII
Limited damage (under $1M)tsunami
- 1792
Kodiak Island
1792 · 229 km away · intensity VII
Limited damage (under $1M)tsunami
- 1854
Gulf Of Alaska
27 Jan 1854 · 229 km away · intensity V
tsunami
- 1866
Kodiak Island, Ak
5 Sep 1866 · 160 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.