QuakeIndex

Earthquake · reviewed by a seismologist

M 3.0ml

Earthquake near Anchorage, AK

No earthquake was likely felt in Anchorage in the 24 hours to 10:10 pm AKST (07:10 UTC). The last one was M 3.5, 39 km (24 mi) SSW, at 4:48 pm AKDT on 27 October 2026, estimated intensity II (weak) in town; 98 felt reports to USGS. Every earthquake near Anchorage

This page: a magnitude 3.0 earthquake was recorded 45 km (28 mi) west-southwest of Anchorage, AK, at 11:12 am AKDT on 23 April 2018 (19:12 UTC), 20 km deep. 4 people have reported feeling it to USGS.

USGS: 20 km E of Beluga, Alaska

45 km (28 mi) WSW of Anchorage, AK

11:12 am AKDT, Apr 23, 2018 · · 20 km deep · released about 950 lb of TNT

Every earthquake near Anchorage Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Anchorage Municipality 77 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
11:12 am AKDT on 23 April 2018 ()
Where
45 km (28 mi) west-southwest of Anchorage, AK · earthquakes near Anchorage
Magnitude
M 3.0 (ml)
Depth
20 km below the surface
Felt
4 reports · strongest reported intensity II
Measured shaking
intensity III (ShakeMap)
Nearest
Anchorage Municipality, 77 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1187 days ago

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

At this magnitude and depth, people at rest would likely notice it out to about 31 km (19 mi) from the epicentre. In Anchorage, 45 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

How big was it?

This earthquake released about 950 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 350,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 16,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 11,000× the energy of this one
  4. This earthquake M 3.0 about 950 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.

For this area

The largest earthquake within 50 km since 2016 was M 4.0 on 2016-11-21 — about 32 times the energy of this one.

Before 2016, the USGS record lists 21 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.8 Southern Alaska · 22 km W of this epicentre
  2. 6.8 4 km NE of Beluga, Alaska · 18 km WNW of this epicentre
  3. 6.4 19 km SSE of Tyonek, Alaska · 30 km SW of this epicentre
  4. 5.8 17 km NW of Beluga, Alaska · 37 km WNW of this epicentre
  5. 5.8 27 km N of Beluga, Alaska · 36 km NNW of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 61.1079, -150.7130. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Anchorage Municipality, AK 77 km (48 mi) E earthquakes near Anchorage Municipality
Kenai Peninsula Borough, AK 120 km (75 mi) SW earthquakes near Kenai Peninsula Borough

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

Aftershocks so far

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

  1. 2.4 7 km SW of Susitna, Alaska
  2. 1.8 18 km SSE of Tyonek, Alaska
  3. 4.2 25 km SW of Susitna, Alaska
  4. 1.6 Southern Alaska
  5. 1.8 22 km ESE of Point Possession, Alaska
  6. 1.6 17 km NE of Beluga, Alaska
  7. 1.9 14 km SSE of Tyonek, Alaska
  8. 3.3 26 km WSW of Susitna, Alaska
  9. 1.5 24 km NE of Beluga, Alaska
  10. 1.5 22 km SSW of Susitna, Alaska
  11. 2.5 9 km WSW of Susitna, Alaska
  12. 1.6 25 km NNW of Beluga, Alaska
  13. 1.5 12 km N of Beluga, Alaska
  14. 1.5 27 km S of Susitna, Alaska
  15. 2.2 15 km NW of Point Possession, 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.