QuakeIndex

Earthquake · reviewed by a seismologist

M 4.0mb

52 km W of Nelson Lagoon, Alaska

· 181 km deep · released about 15 tons of TNT

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10 km30 km60 km120 km N Aleutians East Borough 82 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
Magnitude
M 4.0 (mb)
Depth
181 km below the surface
Felt
no reports yet
Measured shaking
intensity II (ShakeMap)
Nearest
Aleutians East Borough, 82 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 611 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.

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.

  1. Northridge, California 1994 M 6.7 11,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 500× the energy of this one
  3. Magna, Utah 2020 M 5.7 350× the energy of this one
  4. This earthquake M 4.0 about 15 tons of TNT
  5. 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.

Where

Epicentre 55.9852, -162.0499. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Aleutians East Borough, AK 82 km (51 mi) N of here earthquakes near Aleutians East Borough

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

Aftershocks so far

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

  1. 2.8 50 km NW of Nelson Lagoon, Alaska
  2. 2.4 42 km SSW of Nelson Lagoon, Alaska
  3. 2.3 35 km WSW of Nelson Lagoon, Alaska
  4. 2.3 58 km WSW of Nelson Lagoon, Alaska
  5. 2.0 73 km WSW of Nelson Lagoon, Alaska
  6. 1.6 70 km NNE of Cold Bay, Alaska
  7. 1.9 53 km SW of Nelson Lagoon, Alaska
  8. 1.6 47 km SW of Nelson Lagoon, Alaska
  9. 2.4 28 km WSW of Nelson Lagoon, Alaska
  10. 2.2 45 km SSW of Nelson Lagoon, Alaska
  11. 2.2 52 km NNE of Cold Bay, Alaska
  12. 3.1 43 km NNW of Nelson Lagoon, Alaska
  13. 2.8 59 km SW of Nelson Lagoon, Alaska
  14. 3.5 60 km WSW of Nelson Lagoon, Alaska
  15. 2.3 49 km SSW of Nelson Lagoon, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 5.3 on 2016-06-29 — it released about 89 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

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