QuakeIndex

Earthquake · reviewed by a seismologist

M 3.0ml

Earthquake near King Cove, AK

No earthquake was likely felt in King Cove in the 24 hours to 8:34 am AKST (17:34 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 3.0 earthquake was recorded 20 km (13 mi) north of King Cove, AK, at 5:59 pm AKDT on 8 August 2021 (01:59 UTC), 161 km deep.

USGS: 20 km N of King Cove, Alaska

5:59 pm AKDT, Aug 8, 2021 · · 161 km deep · released about 950 lb of TNT

Every earthquake near King Cove Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Aleutians East Borough 19 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
5:59 pm AKDT on 8 August 2021 ()
Where
20 km (13 mi) north of King Cove, AK · earthquakes near King Cove
Magnitude
M 3.0 (ml)
Depth
161 km below the surface
Felt
no reports yet
Nearest
Aleutians East Borough, 19 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1847 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, 20 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 950 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 350,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 16,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 11,000× the energy of this one
  4. This earthquake M 3.0 about 950 lb of TNT

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 350 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 55.2443, -162.2962. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Aleutians East Borough, AK 19 km (12 mi) E earthquakes near Aleutians East Borough

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

Aftershocks so far

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

  1. 2.6 35 km NNE of King Cove, Alaska
  2. 1.6 3 km SSW of Cold Bay, Alaska
  3. 2.7 16 km S of King Cove, Alaska
  4. 1.7 14 km SSE of King Cove, Alaska
  5. 2.8 20 km ENE of Cold Bay, Alaska
  6. 2.0 31 km ESE of King Cove, Alaska
  7. 1.6 10 km SSW of King Cove, Alaska
  8. 2.8 21 km N of King Cove, Alaska
  9. 2.0 55 km NNE of King Cove, Alaska
  10. 1.6 10 km S of Cold Bay, Alaska
  11. 1.7 21 km E of King Cove, Alaska
  12. 1.8 22 km S of Cold Bay, Alaska
  13. 1.8 31 km SE of King Cove, Alaska
  14. 1.6 14 km SSW of Cold Bay, Alaska
  15. 1.8 18 km NNE 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.

On USGS

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