QuakeIndex

Earthquake · reviewed by a seismologist

M 4.1mb

298 km SW of Adak, Alaska

· 14 km deep · released about 21 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 4.1 (mb)
Depth
14 km below the surface
Felt
no reports yet
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2660 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 21 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 7,900× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 350× the energy of this one
  3. Magna, Utah 2020 M 5.7 250× the energy of this one
  4. This earthquake M 4.1 about 21 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 45× 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 50.1974, -179.9566. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 2.9 289 km SW of Adak, Alaska
  2. 3.0 Andreanof Islands, Aleutian Islands, Alaska
  3. 3.0 295 km SW of Adak, Alaska
  4. 2.2 292 km SW of Adak, Alaska
  5. 3.0 Andreanof Islands, Aleutian Islands, Alaska
  6. 3.1 284 km SW of Adak, Alaska
  7. 2.9 285 km SW of Adak, Alaska
  8. 2.0 263 km SW of Adak, Alaska
  9. 2.8 286 km SW of Adak, Alaska
  10. 4.0 299 km SW of Adak, Alaska
  11. 3.4 Andreanof Islands, Aleutian Islands, Alaska
  12. 2.6 Andreanof Islands, Aleutian Islands, Alaska
  13. 3.0 south of the Aleutian Islands
  14. 3.9 Andreanof Islands, Aleutian Islands, Alaska
  15. 3.1 298 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.

On USGS

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