QuakeIndex

Earthquake · reviewed by a seismologist

M 4.0ml

40 km S of Kotzebue, Alaska

· 15 km deep · released about 15 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 4.0 (ml)
Depth
15 km below the surface
Felt
35 reports · strongest reported intensity IV
Measured shaking
intensity III (ShakeMap)
Tsunami
USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
Nearest
Northwest Arctic Borough, 125 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 244 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 35 people have reported feeling it to USGS.

How big was it?

This earthquake released about 15 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 11,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 500× the energy of this one
  3. Magna, Utah 2020 M 5.7 350× the energy of this one
  4. This earthquake M 4.0 about 15 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 32× 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 66.5334, -162.5975. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Northwest Arctic Borough, AK 125 km (77 mi) WSW of here earthquakes near Northwest Arctic Borough

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

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

  1. 2.7 34 km NNE of Deering, Alaska
  2. 2.1 39 km SSW of Kotzebue, 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.