QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9ml

49 km ESE of Knik River, Alaska

· 19 km deep · released about 680 lb of TNT

10 km30 km60 km120 km N Anchorage Municipality 71 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 2.9 (ml)
Depth
19 km below the surface
Felt
1 report · strongest reported intensity I
Nearest
Anchorage Municipality, 71 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 95 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 680 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 22,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 16,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.4× the energy of this one
  4. This earthquake M 2.9 about 680 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 61.3680, -148.0150. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Anchorage Municipality, AK 71 km (44 mi) ENE of here earthquakes near Anchorage Municipality
Matanuska-Susitna Borough, AK 127 km (79 mi) SE of here earthquakes near Matanuska-Susitna Borough
Chugach Census Area, AK 138 km (86 mi) NW of here earthquakes near Chugach Census Area

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

Aftershocks so far

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

  1. 1.5 44 km S of Glacier View, Alaska
  2. 1.5 47 km NE of Whittier, Alaska
  3. 1.5 32 km NNE of Whittier, Alaska
  4. 1.6 42 km ESE of Knik River, Alaska
  5. 2.5 26 km SSE of Chickaloon, Alaska
  6. 1.5 58 km S of Glacier View, Alaska
  7. 2.7 59 km S of Glacier View, Alaska
  8. 2.1 21 km SW of Glacier View, Alaska
  9. 1.6 35 km NNE of Whittier, Alaska
  10. 1.5 60 km S of Glacier View, Alaska
  11. 1.8 31 km NNE of Whittier, Alaska
  12. 1.6 47 km S of Glacier View, Alaska
  13. 2.0 33 km SSW of Glacier View, Alaska
  14. 2.2 59 km WNW of Tatitlek, Alaska
  15. 1.5 14 km S of Glacier View, 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 4.6 on 2018-01-27 — it released about 350 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.