QuakeIndex

Earthquake · reviewed by a seismologist

M 4.0ml

11 km NNE of Cantwell, Alaska

· 9.0 km deep · released about 15 tons of TNT

10 km30 km60 km120 km N Denali Borough 61 km
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
9.0 km below the surface
Felt
20 reports · strongest reported intensity IV
Measured shaking
intensity V (ShakeMap)
USGS impact alert
green
Nearest
Denali Borough, 61 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2122 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 20 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 63.4879, -148.8780. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Denali Borough, AK 61 km (38 mi) ESE of here earthquakes near Denali Borough

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

Aftershocks so far

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

  1. 2.5 23 km WSW of McKinley Park, Alaska
  2. 1.6 8 km E of Healy, Alaska
  3. 1.5 30 km SW of Cantwell, Alaska
  4. 1.6 13 km E of Cantwell, Alaska
  5. 1.5 10 km NNE of Cantwell, Alaska
  6. 1.5 31 km SSW of Cantwell, Alaska
  7. 2.0 17 km W of Healy, Alaska
  8. 1.6 15 km W of Healy, Alaska
  9. 1.7 5 km SSE of Healy, Alaska
  10. 2.1 4 km SE of Healy, Alaska
  11. 2.1 2 km SE of Healy, Alaska
  12. 1.7 5 km WNW of Healy, Alaska
  13. 1.5 23 km ENE of McKinley Park, Alaska
  14. 2.0 7 km S of Cantwell, Alaska
  15. 1.9 26 km ENE of Cantwell, 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 4.1 on 2019-09-25 — it released about 1.4 times the energy of this one.

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

On USGS

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