QuakeIndex

Earthquake · reviewed by a seismologist

M 4.4mb

132 km WSW of Adak, Alaska

· 46 km deep · released about 60 tons of TNT

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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 4.4 (mb)
Depth
46 km below the surface
Felt
no reports yet
Measured shaking
intensity III (ShakeMap)
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1626 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 60 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.4 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 2,800× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 130× the energy of this one
  3. Magna, Utah 2020 M 5.7 89× the energy of this one
  4. This earthquake M 4.4 about 60 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 130× 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 51.3421, -178.3462. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 3.1 131 km WSW of Adak, Alaska
  2. 1.7 133 km WSW of Adak, Alaska
  3. 1.8 137 km WSW of Adak, Alaska
  4. 2.8 131 km W of Adak, Alaska
  5. 1.8 118 km WSW of Adak, Alaska
  6. 2.0 142 km SW of Adak, Alaska
  7. 2.0 124 km WSW of Adak, Alaska
  8. 1.9 Andreanof Islands, Aleutian Islands, Alaska
  9. 1.9 127 km SW of Adak, Alaska
  10. 1.8 139 km WSW of Adak, Alaska
  11. 1.8 112 km WSW of Adak, Alaska
  12. 1.6 124 km SW of Adak, Alaska
  13. 1.7 131 km WSW of Adak, Alaska
  14. 2.1 130 km SW of Adak, Alaska
  15. 1.9 131 km SW of Adak, 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 6.5 on 2018-08-15 — it released about 1,400 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.