QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7ml

22 km SW of Chignik Lake, Alaska

· 4.5 km deep · released about 9.3 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 1.7 (ml)
Depth
4.5 km below the surface
Felt
no reports yet
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2708 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 9.3 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,100,000× the energy of this one
  3. Around the size people start to feel M 3.0 100× the energy of this one
  4. This earthquake M 1.7 about 9.3 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 56.1385, -159.0672. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 1.9 5 km E of Chignik Lake, Alaska
  2. 2.6 36 km ESE of Perryville, Alaska
  3. 2.7 33 km W of Chignik Lake, Alaska
  4. 2.7 14 km SE of Ivanof Bay, Alaska
  5. 1.9 21 km SSE of Chignik Lake, Alaska
  6. 2.5 5 km SW of Perryville, Alaska
  7. 1.5 20 km SSW of Chignik Lake, Alaska
  8. 1.9 6 km SW of Perryville, Alaska
  9. 1.9 19 km WNW of Chignik Lake, Alaska
  10. 1.8 31 km ESE of Perryville, Alaska
  11. 2.3 40 km NW of Chignik Lake, Alaska
  12. 1.7 27 km NNW of Chignik Lake, Alaska
  13. 2.5 17 km WNW of Chignik Lake, Alaska
  14. 4.0 6 km SSE of Ivanof Bay, Alaska
  15. 1.5 9 km SSE of Ivanof Bay, 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.