Earthquake · reviewed by a seismologist
M 4.0mb
64 km SE of King Cove, Alaska
Yes. A magnitude 4.0 earthquake was recorded 64 km SE of King Cove, Alaska, at 2:24 am AKDT on 29 September 2026 (10:24 UTC), 50 km deep.
- When
- Magnitude
- M 4.0 (mb)
- Depth
- 50 km below the surface
- Felt
- no reports yet
- Measured shaking
- intensity II (ShakeMap)
- Nearest
- Aleutians East Borough, 70 km NNW
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 46 days ago
Earthquake alerts for King Cove, AK
Get a notification in this browser when USGS records an earthquake near King Cove, AK. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.
At this magnitude and depth, people at rest would likely notice it out to about 83 km (52 mi) from the epicentre. Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.
How big was it?
This earthquake released about 15 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.0 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 11,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 500× the energy of this one
- Magna, Utah 2020 M 5.7 350× the energy of this one
- This earthquake M 4.0 about 15 tons of TNT
- Around the size people start to feel M 3.0 this one released 32× more
Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.
For this area
The largest earthquake within 50 km since 2016 was M 6.1 on 2020-07-28 — about 1,400 times the energy of this one.
Before 2016, the USGS record lists 48 earthquakes of M5 or more within 50 km; the five largest:
- 7.1 90 km SE of King Cove, Alaska · 29 km ESE of this epicentre
- 7.0 71 km SE of King Cove, Alaska · 10 km S of this epicentre
- 6.8 73 km SW of Sand Point, Alaska · 30 km NE of this epicentre
- 6.7 68 km SSE of King Cove, Alaska · 20 km SW of this epicentre
- 6.6 72 km SE of King Cove, Alaska · 9 km SSE of this epicentre
Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.
Where
Epicentre 54.6600, -161.5901. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Aleutians East Borough, AK | 70 km (44 mi) | NNW | earthquakes near Aleutians East Borough |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
13 earthquakes have been recorded within 50 km since this one.
- 3.5 88 km SSE of King Cove, Alaska
- 3.0 95 km SSE of King Cove, Alaska
- 2.4 99 km SE of King Cove, Alaska
- 2.4 87 km SE of King Cove, Alaska
- 2.8 91 km SSE of King Cove, Alaska
- 2.4 86 km SSE of King Cove, Alaska
- 2.6 103 km SSE of King Cove, Alaska
- 2.5 65 km SSE of King Cove, Alaska
- 2.6 97 km SSE of King Cove, Alaska
- 2.6 57 km SSE of King Cove, Alaska
- 3.0 98 km SSE of King Cove, Alaska
- 2.6 103 km SSE of King Cove, Alaska
- 2.6 99 km SSE of King Cove, Alaska
Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.
Revisions
USGS refines a solution as more stations report. Every change we have seen is listed here.
| What changed | From | To | When |
|---|---|---|---|
| measured intensity | 2.43 | 2.4 |
On USGS
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.