QuakeIndex

Earthquake · reviewed by a seismologist

M 5.2mb

229 km W of Adak, Alaska

· 94 km deep · released about 950 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 5.2 (mb)
Depth
94 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 1151 days ago

This was a moderate earthquake. Shaking at this size can damage poorly built structures close to the epicentre.

How big was it?

This earthquake released about 950 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 6.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 180× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 7.9× the energy of this one
  3. Magna, Utah 2020 M 5.7 5.6× the energy of this one
  4. This earthquake M 5.2 about 950 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 2,000× 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 51.6931, -179.9540. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 2.2 212 km WSW of Adak, Alaska
  2. 2.9 219 km W of Adak, Alaska
  3. 2.3 200 km WSW of Adak, Alaska
  4. 2.4 220 km W of Adak, Alaska
  5. 2.5 237 km WSW of Adak, Alaska
  6. 2.0 209 km W of Adak, Alaska
  7. 2.3 Andreanof Islands, Aleutian Islands, Alaska
  8. 2.3 212 km W of Adak, Alaska
  9. 3.1 235 km WSW of Adak, Alaska
  10. 2.4 223 km W of Adak, Alaska
  11. 2.1 223 km W of Adak, Alaska
  12. 2.4 201 km WSW of Adak, Alaska
  13. 2.3 238 km WSW of Adak, Alaska
  14. 1.8 229 km WSW of Adak, Alaska
  15. 2.0 Andreanof Islands, Aleutian Islands, 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 4.5 on 2016-05-14.

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

On USGS

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