QuakeIndex

Earthquake · reviewed by a seismologist

M 5.2mww

151 km SW of Nikolski, Alaska

· 22 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 (mww)
Depth
22 km below the surface
Felt
no reports yet
Measured shaking
intensity II (ShakeMap)
Tsunami
USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 279 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 52.0018, -170.4883. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 3.2 178 km SW of Nikolski, Alaska
  2. 4.3 157 km SW of Nikolski, Alaska
  3. 4.1 108 km SW of Nikolski, Alaska
  4. 4.1 179 km SW of Nikolski, Alaska
  5. 4.5 158 km SW of Nikolski, Alaska
  6. 3.7 174 km SW of Nikolski, Alaska
  7. 4.7 156 km SW of Nikolski, Alaska
  8. 3.3 112 km SW of Nikolski, Alaska
  9. 4.6 166 km WSW of Nikolski, Alaska
  10. 3.2 154 km SW of Nikolski, Alaska
  11. 2.7 177 km SW of Nikolski, Alaska
  12. 2.8 164 km WSW of Nikolski, Alaska
  13. 4.7 170 km WSW of Nikolski, Alaska
  14. 3.0 138 km SW of Nikolski, Alaska
  15. 3.4 165 km WSW of Nikolski, 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 5.2 on 2017-05-06.

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

On USGS

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