QuakeIndex

Earthquake · reviewed by a seismologist

M 3.9ml

53 km ESE of Pedro Bay, Alaska

· 109 km deep · released about 11 tons of TNT

10 km30 km60 km120 km N Kenai Peninsula Borough 89 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 3.9 (ml)
Depth
109 km below the surface
Felt
6 reports · strongest reported intensity III
Nearest
Kenai Peninsula Borough, 89 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1157 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 6 people have reported feeling it to USGS.

How big was it?

This earthquake released about 11 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.9 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 16,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 710× the energy of this one
  3. Magna, Utah 2020 M 5.7 500× the energy of this one
  4. This earthquake M 3.9 about 11 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 22× 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 59.6880, -153.1738. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Kenai Peninsula Borough, AK 89 km (55 mi) SSW of here earthquakes near Kenai Peninsula Borough

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

Aftershocks so far

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

  1. 1.8 60 km E of Pedro Bay, Alaska
  2. 2.0 47 km ESE of Pedro Bay, Alaska
  3. 1.9 54 km E of Pedro Bay, Alaska
  4. 1.9 55 km E of Pedro Bay, Alaska
  5. 1.7 61 km E of Pedro Bay, Alaska
  6. 2.1 55 km E of Pedro Bay, Alaska
  7. 2.4 58 km E of Pedro Bay, Alaska
  8. 1.7 58 km E of Pedro Bay, Alaska
  9. 1.8 57 km WNW of Anchor Point, Alaska
  10. 2.6 56 km E of Pedro Bay, Alaska
  11. 1.9 54 km E of Pedro Bay, Alaska
  12. 1.8 54 km E of Pedro Bay, Alaska
  13. 1.8 54 km ESE of Pedro Bay, Alaska
  14. 2.0 50 km ESE of Pedro Bay, Alaska
  15. 1.7 62 km E of Pedro 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.

For this area

The largest earthquake within 50 km in our catalogue was M 7.1 on 2016-01-24 — it released about 63,000 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.