Reviewed by USGSAlaska117y ago
M7.0 earthquake 101 km S of Adak, Alaska
Friday, September 9, 1910, 01:13:16 UTC · 50.978°N, 176.351°W
A magnitude 7.0 earthquake struck 101 km S of Adak, Alaska on Friday, September 9, 1910, 01:13:16 UTC, at a depth of 35.0 km (shallow). It is the strongest earthquake within 300 km since an M7.2 on March 22, 1905.
- Magnitude
- 7.0
- Major · mw
- Depth
- 35 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
511 kilotons of TNT
That is about 34 times the Hiroshima bomb. It released about 1,072 times the energy of a magnitude 5.0.
Tectonic setting
43 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
35 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 6 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.65 km WNW of Adak, AlaskaFebruary 14, 1905 · 104 km N of this epicenter
- 7.2238 km WSW of Adak, AlaskaMarch 22, 1905 · 246 km W of this epicenter
- 6.9182 km SSE of Atka, AlaskaJanuary 27, 1906 · 250 km E of this epicenter
- 6.7254 km SW of Adak, AlaskaSeptember 14, 1905 · 228 km W of this epicenter
- 6.776 km SSE of Adak, AlaskaDecember 10, 1905 · 32 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 1 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1905M7.9
Andreanof Islands
14 Feb 1905 · 157 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.