27 km ESE of Adak, Alaska

Yes. A magnitude 5.2 earthquake was recorded 27 km ESE of Adak, Alaska at 05:00 UTC on 2017-08-01, 61 km deep. 2 people have reported feeling it to USGS.

2017-08-01 05:00 UTC · 61 km deep · released about 950 tons of TNT

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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: 2017-08-01 05:00 UTC
Magnitude: M 5.2 (mb)
Depth: 61 km below the surface
Felt: 2 reports · strongest reported intensity IV
Measured shaking: intensity IV (ShakeMap)
USGS impact alert: green
Tsunami: USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
Status: Reviewed by a seismologist

USGS · last changed by USGS 1192 days ago · we first saw it 1192 days ago

This was a moderate earthquake. Shaking at this size can damage poorly built structures close to the epicentre.

At this magnitude and depth, people at rest would likely notice it out to about 210 km (130 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 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 6.2 would have released about 32 times as much.

Northridge, California 1994 M 6.7 180× the energy of this one
Mineral, Virginia 2011 M 5.8 7.9× the energy of this one
Magna, Utah 2020 M 5.7 5.6× the energy of this one
This earthquake M 5.2 about 950 tons of TNT
Around the size people start to feel M 3.0 this one released 2,000× more

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 (31 mi) since our catalogue begins in 2016. The previous largest was M 5.0 on 2016-11-14.

Before 2016, the USGS record lists 88 earthquakes of M5 or more within 50 km; the five largest:

7.6 5 km WNW of Adak, Alaska · 32 km WNW of this epicentre Feb 14, 1905
6.7 52 km ESE of Adak, Alaska · 27 km SE of this epicentre Nov 4, 1977
6.5 56 km E of Adak, Alaska · 31 km ENE of this epicentre Jul 17, 1914
6.5 46 km ESE of Adak, Alaska · 19 km E of this epicentre Jan 5, 1961
6.5 70 km SE of Adak, Alaska · 48 km SSE of this epicentre Sep 3, 2010

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

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Aftershocks so far

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

2.5 66 km SE of Adak, Alaska 02:09 UTC
2.5 42 km SSE of Adak, Alaska 08:12 UTC
1.9 57 km SSE of Adak, Alaska 04:08 UTC
1.9 55 km ESE of Adak, Alaska 04:29 UTC
1.9 36 km NE of Adak, Alaska 19:13 UTC
1.7 Andreanof Islands, Aleutian Islands, Alaska 07:45 UTC
2.1 43 km NNE of Adak, Alaska 04:39 UTC
2.9 39 km NE of Adak, Alaska 16:43 UTC
2.0 36 km NE of Adak, Alaska 14:06 UTC
2.8 34 km ENE of Adak, Alaska 12:58 UTC
1.8 42 km SSE of Adak, Alaska 08:32 UTC
1.9 65 km SE of Adak, Alaska 13:32 UTC
1.6 48 km S of Adak, Alaska 06:48 UTC
2.3 58 km ESE of Adak, Alaska 11:43 UTC
2.1 57 km SE of Adak, Alaska 16:24 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 03:06 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.