Reviewed by USGSAlaska11y ago
M3.7 earthquake 79 km SE of Atka, Alaska
Thursday, November 19, 2015, 04:52:38 UTC · 51.708°N, 173.352°W
A magnitude 3.7 earthquake struck 79 km SE of Atka, Alaska on Thursday, November 19, 2015, 04:52:38 UTC, at a depth of 41.1 km (shallow).
- Magnitude
- 3.7
- Minor · mb
- Depth
- 41 km
- Shallow
- Felt reports
- 0
- Max intensity I
- 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
5 tons of TNT
That is about 1/2,814 of the Hiroshima bomb. A magnitude 5.0 releases about 89 times more energy.
Tectonic setting
81 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 M3.1 on November 29, 2015. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 2.572 km SSE of Atka, Alaska10y ago · 46 km W of this epicenter
- 2.664 km ESE of Atka, Alaska10y ago · 41 km N of this epicenter
- 3.172 km ESE of Atka, Alaska10y ago · 23 km N of this epicenter
- 2.9121 km ESE of Atka, Alaska10y ago · 46 km E of this epicenter
- 2.585 km SSE of Atka, Alaska11y ago · 24 km SW of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 916 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.61957 Atka, Alaska EarthquakeMarch 9, 1957 · 159 km W of this epicenter
- 8.01986 Atka, Alaska EarthquakeMay 7, 1986 · 100 km W of this epicenter
- 7.977 km WSW of Adak, AlaskaJune 10, 1996 · 296 km W of this epicenter
- 7.8234 km SSW of Nikolski, AlaskaMarch 7, 1929 · 263 km E of this epicenter
- 7.65 km WNW of Adak, AlaskaFebruary 14, 1905 · 231 km W of this epicenter
- 7.4133 km WNW of Nikolski, AlaskaApril 18, 1916 · 265 km NE of this epicenter
- 7.346 km SSW of Adak, AlaskaJune 10, 1996 · 243 km W of this epicenter
- 7.3Fox Islands, Aleutian Islands, AlaskaJune 24, 2011 · 111 km E of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 14 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 2 recorded deaths. The most severe:
- 1957M8.6
Alaska
9 Mar 1957 · 159 km away
2 deathsSevere damage ($5–24M)tsunami
- 1986M8.0
Aleutian Islands: Adak
7 May 1986 · 100 km away · intensity VI
Moderate damage ($1–5M)tsunami
- 1901M7.8
Aleutian Islands: Fox Islands
31 Dec 1901 · 164 km away
Limited damage (under $1M)tsunami
- 1996M7.9
Andreanof Islands
10 Jun 1996 · 296 km away · intensity VI
tsunami
- 1907M7.8
Aleutian Islands
2 Sep 1907 · 266 km away
- 1929M7.8
Aleutian Islands: Fox Islands
7 Mar 1929 · 246 km away · intensity V
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.