85 km ENE of Akutan, Alaska

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 8 km (5 mi) from the epicentre. 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 15 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 1,000,000× the energy of this one
2. Magna, Utah 2020 M 5.7 710,000× the energy of this one
3. Around the size people start to feel M 3.0 63× the energy of this one
4. This earthquake M 1.8 about 15 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 4.9 on 2017-05-12 — about 45,000 times the energy of this one.

Before 2016, the USGS record lists 11 earthquakes of M5 or more within 50 km; the five largest:

1. 6.5 79 km SW of False Pass, Alaska · 30 km ESE of this epicentre Nov 19, 1993
2. 6.4 60 km NE of Akutan, Alaska · 34 km WNW of this epicentre Jul 27, 1944
3. 5.8 95 km E of Akutan, Alaska · 37 km SSE of this epicentre Dec 30, 1965
4. 5.8 85 km SW of False Pass, Alaska · 33 km SE of this epicentre Jan 3, 1998
5. 5.6 87 km SSW of False Pass, Alaska · 37 km SE of this epicentre Dec 27, 1983

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 54.4206, -164.5618. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 2.2 61 km ENE of Akutan, Alaska 12:14 UTC
2. 2.0 86 km E of Akutan, Alaska 23:58 UTC
3. 1.7 85 km E of Akutan, Alaska 14:35 UTC
4. 2.0 78 km E of Akutan, Alaska 05:51 UTC
5. 2.2 67 km ESE of Akutan, Alaska 19:49 UTC
6. 2.1 94 km E of Akutan, Alaska 17:05 UTC
7. 2.7 83 km E of Akutan, Alaska 03:43 UTC
8. 2.2 92 km SW of False Pass, Alaska 06:08 UTC
9. 2.8 70 km SW of False Pass, Alaska 19:16 UTC
10. 2.1 48 km E of Akutan, Alaska 00:19 UTC
11. 1.8 65 km E of Akutan, Alaska 05:47 UTC
12. 2.9 87 km E of Akutan, Alaska 05:45 UTC
13. 2.1 99 km SSW of False Pass, Alaska 16:37 UTC
14. 2.9 69 km ENE of Akutan, Alaska 02:25 UTC
15. 2.1 89 km SSW of False Pass, Alaska 19:11 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 09:19 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.