Earthquake near Kodiak, AK

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 Kodiak, 46 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 170 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 89,000× the energy of this one
2. Magna, Utah 2020 M 5.7 63,000× the energy of this one
3. Around the size people start to feel M 3.0 5.6× the energy of this one
4. This earthquake M 2.5 about 170 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 4.1 on 2017-03-05 — about 250 times the energy of this one.

Before 2016, the USGS record lists 12 earthquakes of M5 or more within 50 km; the five largest:

1. 6.2 53 km ESE of Old Harbor, Alaska · 40 km SSW of this epicentre Mar 28, 1964
2. 5.9 25 km E of Old Harbor, Alaska · 46 km WSW of this epicentre Mar 28, 1964
3. 5.8 55 km SE of Chiniak, Alaska · 40 km ESE of this epicentre Mar 28, 1964
4. 5.6 39 km ESE of Chiniak, Alaska · 34 km ENE of this epicentre Mar 28, 1964
5. 5.6 47 km ESE of Chiniak, Alaska · 44 km ENE of this epicentre Apr 13, 1964

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 57.3815, -152.2405. Map © OpenStreetMap contributors.

Nearby places

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

Aftershocks so far

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

1. 2.4 13 km S of Chiniak, Alaska 00:17 UTC
2. 2.4 11 km ESE of Womens Bay, Alaska 02:00 UTC
3. 2.3 30 km SSW of Chiniak, Alaska 12:21 UTC
4. 2.4 25 km S of Womens Bay, Alaska 21:30 UTC
5. 2.4 12 km ESE of Kodiak, Alaska 12:11 UTC
6. 2.2 29 km ESE of Chiniak, Alaska 04:45 UTC
7. 1.8 14 km SSE of Womens Bay, Alaska 04:38 UTC
8. 2.1 17 km SSE of Chiniak, Alaska 12:21 UTC
9. 1.8 37 km E of Old Harbor, Alaska 09:48 UTC
10. 2.7 22 km S of Chiniak, Alaska 17:21 UTC
11. 2.4 17 km SW of Chiniak, Alaska 20:14 UTC
12. 2.5 24 km E of Chiniak, Alaska 22:56 UTC
13. 4.2 24 km SSW of Chiniak, Alaska 02:36 UTC
14. 2.1 3 km ESE of Kodiak, Alaska 08:02 UTC
15. 2.6 37 km SE of Chiniak, Alaska 09:22 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 21:39 UTC. QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

On USGS

• The official USGS event page — the source of record for every value above
• Did you feel it? Report it to USGS — reports go to USGS, not to us
• ShakeMap for this event, when USGS has produced one

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.