QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

Earthquake near King Cove, AK

No earthquake was likely felt in King Cove in the 24 hours to 11:05 am AKST (20:05 UTC). The last one was M 5.0, 171 km (106 mi) SSW, at 12:14 pm AKDT on 29 October 2026, estimated intensity II (weak) in town. Every earthquake near King Cove

This page: a magnitude 3.1 earthquake was recorded 43 km (27 mi) north-northwest of King Cove, AK, at 9:49 pm AKDT on 28 July 2021 (05:49 UTC), 171 km deep.

USGS: 32 km NNE of Cold Bay, Alaska

9:49 pm AKDT, Jul 28, 2021 · · 171 km deep · released about 1,300 lb of TNT

Every earthquake near King Cove Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Aleutians East Borough 37 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
9:49 pm AKDT on 28 July 2021 ()
Where
43 km (27 mi) north-northwest of King Cove, AK · earthquakes near King Cove
Magnitude
M 3.1 (ml)
Depth
171 km below the surface
Felt
no reports yet
Nearest
Aleutians East Borough, 37 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1868 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In King Cove, 43 km away, the estimate is intensity I (not felt). 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 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 250,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,900× the energy of this one
  4. This earthquake M 3.1 about 1,300 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.4× 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 4.7 on 2016-09-06 — about 250 times the energy of this one.

Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.

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 55.4417, -162.4712. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Aleutians East Borough, AK 37 km (23 mi) SE earthquakes near Aleutians East Borough

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

56 earthquakes have been recorded within 50 km since this one.

  1. 1.9 2 km ESE of King Cove, Alaska
  2. 2.3 47 km NNE of King Cove, Alaska
  3. 1.8 4 km E of King Cove, Alaska
  4. 2.6 36 km NNE of King Cove, Alaska
  5. 1.8 4 km E of King Cove, Alaska
  6. 1.9 Alaska Peninsula
  7. 1.8 2 km NE of King Cove, Alaska
  8. 2.6 19 km NNW of King Cove, Alaska
  9. 2.0 33 km NNE of King Cove, Alaska
  10. 2.1 34 km NNE of King Cove, Alaska
  11. 2.2 33 km NE of King Cove, Alaska
  12. 2.6 16 km SW of Cold Bay, Alaska
  13. 1.6 13 km NE of King Cove, Alaska
  14. 1.5 15 km E of King Cove, Alaska
  15. 2.6 13 km S of Cold Bay, 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.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.