QuakeIndex

Earthquake · reviewed by a seismologist

M 5.0mb

87 km ENE of Ouzinkie, Alaska

· 25 km deep · released about 480 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 5.0 (mb)
Depth
25 km below the surface
Felt
31 reports · strongest reported intensity IV
Measured shaking
intensity IV (ShakeMap)
USGS impact alert
green
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 1903 days ago

This was a moderate earthquake. Shaking at this size can damage poorly built structures close to the epicentre. 31 people have reported feeling it to USGS.

How big was it?

This earthquake released about 480 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 6.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 350× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 16× the energy of this one
  3. Magna, Utah 2020 M 5.7 11× the energy of this one
  4. This earthquake M 5.0 about 480 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 1,000× 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 58.2809, -151.1795. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 1.6 75 km ENE of Kodiak, Alaska
  2. 2.2 81 km ENE of Ouzinkie, Alaska
  3. 1.6 Kodiak Island region, Alaska
  4. 1.7 68 km ENE of Ouzinkie, Alaska
  5. 1.8 57 km ENE of Ouzinkie, Alaska
  6. 1.8 63 km ENE of Ouzinkie, Alaska
  7. 2.0 78 km ENE of Ouzinkie, Alaska
  8. 1.8 72 km ENE of Ouzinkie, Alaska
  9. 2.9 95 km ENE of Kodiak, Alaska
  10. 2.0 70 km ENE of Ouzinkie, Alaska
  11. 2.5 90 km ENE of Ouzinkie, Alaska
  12. 1.9 77 km ENE of Ouzinkie, Alaska
  13. 2.0 73 km ENE of Ouzinkie, Alaska
  14. 1.9 56 km ENE of Ouzinkie, Alaska
  15. 3.2 93 km NE of Ouzinkie, 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.