QuakeIndex

Earthquake · reviewed by a seismologist

M 5.3mw

53 km SW of Tatitlek, Alaska

Yes. A magnitude 5.3 earthquake was recorded 53 km SW of Tatitlek, Alaska, at 1:18 pm AKST on 27 November 2017 (22:18 UTC), 17 km deep. 1,033 people have reported feeling it to USGS.

· 17 km deep · released about 1.3 kilotons of TNT

10 km30 km60 km120 km N Chugach Census Area 68 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
Magnitude
M 5.3 (mw)
Depth
17 km below the surface
Felt
1,033 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.
Nearest
Chugach Census Area, 68 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1191 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 231 km (144 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 1.3 kilotons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 6.3 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 130× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 5.6× the energy of this one
  3. Magna, Utah 2020 M 5.7 4× the energy of this one
  4. This earthquake M 5.3 about 1.3 kilotons of TNT
  5. Around the size people start to feel M 3.0 this one released 2,800× 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 4.3 on 2017-07-11.

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

  1. 9.2 The 1964 Prince William Sound, Alaska Earthquake · 40 km N of this epicentre
  2. 7.0 52 km NE of Chenega, Alaska · 22 km SSE of this epicentre
  3. 6.7 Prince William Sound, Alaska · 25 km ENE of this epicentre
  4. 6.4 Prince William Sound, Alaska · 15 km SE of this epicentre
  5. 6.4 46 km WNW of Tatitlek, Alaska · 47 km N 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 60.5552, -147.4303. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Chugach Census Area, AK 68 km (42 mi) E earthquakes near Chugach Census Area
Anchorage Municipality, AK 122 km (76 mi) NW earthquakes near Anchorage Municipality

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

Aftershocks so far

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

  1. 1.8 51 km W of Tatitlek, Alaska
  2. 2.2 47 km W of Tatitlek, Alaska
  3. 1.5 47 km NNE of Chenega, Alaska
  4. 1.6 32 km SSW of Tatitlek, Alaska
  5. 1.5 36 km NNE of Chenega, Alaska
  6. 1.5 54 km SW of Tatitlek, Alaska
  7. 2.0 55 km NNE of Chenega, Alaska
  8. 2.2 46 km SSW of Tatitlek, Alaska
  9. 1.6 48 km W of Tatitlek, Alaska
  10. 1.6 35 km NNE of Chenega, Alaska
  11. 1.5 33 km NE of Chenega, Alaska
  12. 1.8 50 km W of Tatitlek, Alaska
  13. 2.2 55 km NE of Chenega, Alaska
  14. 1.6 50 km NE of Chenega, Alaska
  15. 1.9 52 km NE of Chenega, 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.