QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

231 km S of Sand Point, Alaska

· 10 km deep · released about 1,300 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 3.1 (ml)
Depth
10 km below the surface
Felt
no reports yet
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2069 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

How big was it?

This earthquake released about 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 250,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,900× the energy of this one
  4. This earthquake M 3.1 about 1,300 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.4× 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 53.2584, -160.4619. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 2.9 205 km SSE of King Cove, Alaska
  2. 3.0 223 km S of Sand Point, Alaska
  3. 3.1 223 km SSE of King Cove, Alaska
  4. 2.8 203 km S of Sand Point, Alaska
  5. 3.0 223 km S of Sand Point, Alaska
  6. 2.6 229 km SSE of King Cove, Alaska
  7. 2.9 south of Alaska
  8. 2.6 217 km S of Sand Point, Alaska
  9. 2.7 238 km SSE of King Cove, Alaska
  10. 3.1 south of Alaska
  11. 3.0 206 km S of Sand Point, Alaska
  12. 3.2 215 km SSE of King Cove, Alaska
  13. 3.1 210 km S of Sand Point, Alaska
  14. 2.7 south of Alaska
  15. 3.2 229 km S of Sand Point, 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 5.5 on 2020-07-05 — it released about 4,000 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.