229 km S of Unalaska, Alaska

Yes. A magnitude 3.0 earthquake was recorded 229 km S of Unalaska, Alaska at 22:59 UTC on 2020-09-13, 10 km deep.

2020-09-13 22:59 UTC · 10 km deep · released about 950 lb of TNT

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: 2020-09-13 22:59 UTC
Magnitude: M 3.0 (ml)
Depth: 10 km below the surface
Felt: no reports yet
Status: Reviewed by a seismologist

USGS · last changed by USGS 2184 days ago · we first saw it 2184 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, people at rest would likely notice it out to about 35 km (22 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 950 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

Northridge, California 1994 M 6.7 350,000× the energy of this one
Mineral, Virginia 2011 M 5.8 16,000× the energy of this one
Magna, Utah 2020 M 5.7 11,000× the energy of this one
This earthquake M 3.0 about 950 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 5.2 on 2019-08-03 — about 2,000 times the energy of this one.

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

7.0 203 km SSE of Unalaska, Alaska · 49 km NE of this epicentre Aug 22, 1940
6.5 183 km S of Unalaska, Alaska · 50 km NNW of this epicentre Apr 19, 1957
6.0 221 km S of Unalaska, Alaska · 9 km NNE of this epicentre Mar 17, 1957
6.0 218 km SE of Nikolski, Alaska · 24 km WSW of this epicentre Aug 7, 2004
5.4 214 km ESE of Nikolski, Alaska · 16 km WNW of this epicentre Apr 8, 1975

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

Map loads when it scrolls into view

Aftershocks so far

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

2.0 218 km SSE of Unalaska, Alaska 17:10 UTC
3.2 192 km ESE of Nikolski, Alaska 13:46 UTC
2.6 184 km S of Unalaska, Alaska 19:26 UTC
3.5 185 km ESE of Nikolski, Alaska 01:48 UTC
2.4 194 km S of Unalaska, Alaska 06:15 UTC
2.3 197 km SSE of Unalaska, Alaska 18:59 UTC
2.7 209 km SSE of Unalaska, Alaska 14:33 UTC
2.1 226 km SE of Nikolski, Alaska 09:44 UTC
2.0 205 km S of Unalaska, Alaska 09:38 UTC
2.6 192 km ESE of Nikolski, Alaska 18:38 UTC
2.3 200 km SSE of Unalaska, Alaska 12:29 UTC
3.1 227 km SE of Nikolski, Alaska 08:02 UTC
2.7 207 km S of Unalaska, Alaska 16:10 UTC
2.6 191 km S of Unalaska, Alaska 09:11 UTC
2.8 192 km SSE of Unalaska, Alaska 22:14 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 13:48 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.