QuakeIndex

Earthquake · reviewed by a seismologist

M 4.4ml

158 km ESE of Chignik, Alaska

· 56 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 (ml)
Depth
56 km below the surface
Felt
no reports yet
Measured shaking
intensity III (ShakeMap)
USGS impact alert
green
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1144 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 55.8305, -155.9946. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 2.4 137 km E of Chignik, Alaska
  2. 2.7 132 km SW of Akhiok, Alaska
  3. 2.1 south of Alaska
  4. 2.5 130 km SW of Akhiok, Alaska
  5. 3.4 119 km ESE of Chignik, Alaska
  6. 3.0 153 km ESE of Chignik, Alaska
  7. 2.9 126 km SW of Akhiok, AK
  8. 2.4 130 km SW of Akhiok, Alaska
  9. 2.8 142 km E of Chignik, Alaska
  10. 2.5 172 km ESE of Chignik, Alaska
  11. 3.0 136 km E of Chignik, Alaska
  12. 2.0 139 km E of Chignik, Alaska
  13. 2.6 134 km ESE of Chignik, Alaska
  14. 2.0 131 km E of Chignik, Alaska
  15. 3.6 155 km SW of Akhiok, 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.