QuakeIndex

Earthquake · reviewed by a seismologist

M 3.6mb

Earthquake near Dutch Harbor, AK

No earthquake was likely felt in Dutch Harbor in the 24 hours to 4:29 pm AKST (01:29 UTC). The last one was M 4.4, 117 km (73 mi) ESE, at 3:00 pm AKST on 11 November 2026, estimated intensity II (weak) in town. Every earthquake near Dutch Harbor

This page: a magnitude 3.6 earthquake was recorded 38 km (24 mi) north-northeast of Dutch Harbor, AK, at 11:27 pm AKDT on 12 April 2017 (07:27 UTC), 117 km deep.

USGS: 30 km W of Akutan, Alaska

11:27 pm AKDT, Apr 12, 2017 · · 117 km deep · released about 3.8 tons of TNT

Every earthquake near Dutch Harbor Felt it? Tell USGS Check my area
10 km30 km60 km120 km N
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
11:27 pm AKDT on 12 April 2017 ()
Where
38 km (24 mi) north-northeast of Dutch Harbor, AK · earthquakes near Dutch Harbor
Magnitude
M 3.6 (mb)
Depth
117 km below the surface
Felt
no reports yet
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1194 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 it was probably too small to be felt, even directly above it. In Dutch Harbor, 38 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 3.8 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.6 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 45,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 2,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 1,400× the energy of this one
  4. This earthquake M 3.6 about 3.8 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 7.9× 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.

For this area

The largest earthquake within 50 km since 2016 was M 4.0 on 2016-08-29 — about 4 times the energy of this one.

Before 2016, the USGS record lists 9 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.3 23 km NE of Akutan, Alaska · 45 km ENE of this epicentre
  2. 5.9 27 km WNW of Dutch Harbor, Alaska · 50 km WSW of this epicentre
  3. 5.9 13 km NE of Dutch Harbor, Alaska · 25 km SSW of this epicentre
  4. 5.3 15 km E of Akutan, Alaska · 45 km E of this epicentre
  5. 5.3 22 km ENE of Dutch Harbor, Alaska · 22 km S 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 54.1777, -166.2301. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 2.1 13 km WSW of Akutan, Alaska
  2. 1.7 14 km W of Akutan, Alaska
  3. 2.4 6 km WSW of Unalaska, Alaska
  4. 2.0 22 km S of Akutan, Alaska
  5. 1.9 23 km S of Akutan, Alaska
  6. 1.9 38 km ESE of Unalaska, Alaska
  7. 1.5 26 km SE of Unalaska, Alaska
  8. 1.7 3 km WNW of Dutch Harbor, Alaska
  9. 1.5 16 km WSW of Akutan, Alaska
  10. 2.0 22 km W of Akutan, Alaska
  11. 2.7 68 km NW of Akutan, Alaska
  12. 1.5 15 km W of Akutan, Alaska
  13. 1.9 32 km SSW of Akutan, Alaska
  14. 1.7 9 km WSW of Akutan, Alaska
  15. 1.6 Fox Islands, Aleutian Islands, 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.