QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

Earthquake near Sitka, AK

No earthquake was likely felt in Sitka in the 24 hours to 1:40 pm AKST (22:40 UTC). The last one was M 3.9, 65 km (40 mi) W, at 12:45 pm AKST on 17 January 2026, estimated intensity II (weak) in town; 28 felt reports to USGS. Every earthquake near Sitka

This page: a magnitude 1.6 earthquake was recorded 24 km (15 mi) west of Sitka, AK, at 10:31 pm AKDT on 30 May 2023 (06:31 UTC), 12 km deep.

USGS: 24 km W of Sitka, Alaska

10:31 pm AKDT, May 30, 2023 · · 12 km deep · released about 7.6 lb of TNT

Every earthquake near Sitka Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Sitka City and Borough 27 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
10:31 pm AKDT on 30 May 2023 ()
Where
24 km (15 mi) west of Sitka, AK · earthquakes near Sitka
Magnitude
M 1.6 (ml)
Depth
12 km below the surface
Felt
no reports yet
Nearest
Sitka City and Borough, 27 km NE
Nearest mapped fault
Fairweather fault system, 22 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1252 days ago

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

At this magnitude and depth it was probably too small to be felt, even directly above it. In Sitka, 24 km away, the estimate is intensity I (not felt). 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 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 4.2 on 2020-11-23 — about 7,900 times the energy of this one.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 7.6 55 km SW of Sitka, Alaska · 44 km SSW 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 57.0596, -135.7328. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Sitka City and Borough, AK 27 km (17 mi) NE earthquakes near Sitka City and 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. 2.1 60 km WNW of Sitka, Alaska
  2. 1.9 58 km SW of Sitka, Alaska
  3. 2.1 57 km WNW of Sitka, Alaska
  4. 2.0 62 km WNW of Sitka, Alaska
  5. 1.9 48 km W of Sitka, Alaska
  6. 1.6 44 km W of Sitka, Alaska
  7. 1.6 53 km W of Sitka, Alaska
  8. 1.5 52 km W of Sitka, Alaska
  9. 1.9 57 km WNW of Sitka, Alaska
  10. 2.2 19 km WNW of Sitka, Alaska
  11. 1.9 55 km WNW of Sitka, Alaska
  12. 2.8 58 km WNW of Sitka, Alaska
  13. 1.8 58 km WNW of Sitka, Alaska
  14. 1.9 59 km WNW of Sitka, Alaska
  15. 1.7 58 km WNW of Sitka, 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.