QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4ml

240 km SSE of Old Harbor, Alaska

· 16 km deep · released about 120 lb 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 2.4 (ml)
Depth
16 km below the surface
Felt
no reports yet
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1850 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 120 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 130,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 89,000× the energy of this one
  3. Around the size people start to feel M 3.0 7.9× the energy of this one
  4. This earthquake M 2.4 about 120 lb of TNT

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 55.3780, -151.2421. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 2.8 228 km SSE of Old Harbor, Alaska
  2. 3.2 203 km SSE of Old Harbor, Alaska
  3. 2.8 205 km SSE of Old Harbor, Alaska
  4. 2.4 218 km SSE of Old Harbor, Alaska
  5. 3.0 202 km SSE of Old Harbor, Alaska
  6. 3.3 264 km SSE of Old Harbor, Alaska
  7. 2.5 218 km SSE of Old Harbor, Alaska
  8. 2.3 217 km SSE of Old Harbor, Alaska
  9. 2.2 225 km SSE of Old Harbor, Alaska
  10. 2.3 253 km SSE of Old Harbor, Alaska
  11. 3.4 240 km SSE of Old Harbor, Alaska
  12. 2.9 230 km SSE of Old Harbor, Alaska
  13. 2.7 277 km SSE of Old Harbor, Alaska
  14. 3.2 south of Alaska
  15. 2.9 209 km SSE of Old Harbor, 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.