QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

Earthquake near Unalaska, AK

No earthquake was likely felt in Unalaska in the 24 hours to 7:48 pm AKST (04:48 UTC). The last one was M 4.4, 117 km (72 mi) ESE, at 3:00 pm AKST on 11 November 2026, estimated intensity II (weak) in town. Every earthquake near Unalaska

This page: a magnitude 1.6 earthquake was recorded 3 km (2 mi) east-northeast of Unalaska, AK, at 12:21 pm AKDT on 13 June 2025 (20:21 UTC), 8.6 km deep.

USGS: 2 km ENE of Unalaska, Alaska

12:21 pm AKDT, Jun 13, 2025 · · 8.6 km deep · released about 7.6 lb of TNT

Every earthquake near Unalaska Felt it? Tell USGS Check my area
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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
12:21 pm AKDT on 13 June 2025 ()
Where
3 km (2 mi) east-northeast of Unalaska, AK · earthquakes near Unalaska
Magnitude
M 1.6 (ml)
Depth
8.6 km below the surface
Felt
no reports yet
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 512 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 7 km (4 mi) from the epicentre. In Unalaska, 3 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.

Likely felt in: Unalaska 3 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 7.6 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,400,000× the energy of this one
  3. Around the size people start to feel M 3.0 130× the energy of this one
  4. This earthquake M 1.6 about 7.6 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 4.8 on 2020-03-30 — about 63,000 times the energy of this one.

Before 2016, the USGS record lists 13 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.1 39 km S of Akutan, Alaska · 49 km ESE of this epicentre
  2. 6.2 36 km ESE of Unalaska, Alaska · 35 km ESE of this epicentre
  3. 5.9 27 km WNW of Dutch Harbor, Alaska · 30 km WNW of this epicentre
  4. 5.9 13 km NE of Dutch Harbor, Alaska · 12 km NE of this epicentre
  5. 5.4 26 km WSW of Dutch Harbor, Alaska · 29 km WSW 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 53.8841, -166.4967. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 2.6 16 km SE of Unalaska, Alaska
  2. 1.9 33 km SW of Unalaska, Alaska
  3. 1.9 26 km SE of Unalaska, Alaska
  4. 1.9 21 km ESE of Unalaska, Alaska
  5. 1.6 30 km SSW of Unalaska, Alaska
  6. 2.6 24 km SE of Unalaska, Alaska
  7. 2.6 34 km SW of Unalaska, Alaska
  8. 1.6 35 km SSW of Unalaska, Alaska
  9. 1.5 27 km SE of Unalaska, Alaska
  10. 3.3 29 km SE of Unalaska, Alaska
  11. 3.4 38 km S of Unalaska, Alaska
  12. 3.3 25 km SE of Unalaska, Alaska
  13. 1.8 20 km WSW of Akutan, Alaska
  14. 1.5 37 km S of Unalaska, Alaska
  15. 2.8 31 km SE of Unalaska, 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.