QuakeIndex

Earthquake · reviewed by a seismologist

M 4.0mwr

149 km SW of Yakutat, Alaska

· 10 km deep · released about 15 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N
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 (mwr)
Depth
10 km below the surface
Felt
no reports yet
Nearest mapped fault
Transition fault, 23 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2165 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.

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 58.5781, -141.5408. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 2.8 132 km SW of Yakutat, Alaska
  2. 2.5 188 km SW of Yakutat, Alaska
  3. 2.4 123 km SW of Yakutat, Alaska
  4. 1.9 139 km WSW of Yakutat, Alaska
  5. 2.3 129 km SW of Yakutat, Alaska
  6. 2.2 127 km SW of Yakutat, Alaska
  7. 2.5 134 km SW of Yakutat, Alaska
  8. 2.0 143 km SW of Yakutat, Alaska
  9. 2.5 132 km SW of Yakutat, Alaska
  10. 2.0 144 km SSW of Yakutat, Alaska
  11. 2.1 169 km SW of Yakutat, Alaska
  12. 2.1 163 km SW of Yakutat, Alaska
  13. 2.7 142 km SW of Yakutat, Alaska
  14. 2.6 152 km SW of Yakutat, Alaska
  15. 1.9 176 km SW of Yakutat, 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.