QuakeIndex

Earthquake · reviewed by a seismologist

M 2.2ml

54 km NW of Tatitlek, Alaska

Yes. A magnitude 2.2 earthquake was recorded 54 km NW of Tatitlek, Alaska, at 12:59 am AKDT on 7 August 2018 (08:59 UTC), 10 km deep.

· 10 km deep · released about 60 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Anchorage Municipality 95 kmChugach Census Area 102 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 2.2 (ml)
Depth
10 km below the surface
Felt
no reports yet
Nearest
Anchorage Municipality, 95 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1185 days ago

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 15 km (9 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 60 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.2 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 250,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 180,000× the energy of this one
  3. Around the size people start to feel M 3.0 16× the energy of this one
  4. This earthquake M 2.2 about 60 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 22 earthquakes of M5 or more within 50 km; the five largest:

  1. 9.2 The 1964 Prince William Sound, Alaska Earthquake · 28 km SSE of this epicentre
  2. 6.8 31 km SSW of Glacier View, Alaska · 46 km NNW of this epicentre
  3. 6.6 57 km ENE of Whittier, Alaska · 18 km SW of this epicentre
  4. 6.6 37 km WNW of Tatitlek, Alaska · 17 km SE of this epicentre
  5. 6.4 37 km SSE of Glacier View, Alaska · 39 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 61.1413, -147.5146. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Anchorage Municipality, AK 95 km (59 mi) W earthquakes near Anchorage Municipality
Chugach Census Area, AK 102 km (63 mi) SE earthquakes near Chugach Census Area

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

Aftershocks so far

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

  1. 1.8 63 km S of Glacier View, Alaska
  2. 1.6 64 km S of Glacier View, Alaska
  3. 2.3 46 km WSW of Tatitlek, Alaska
  4. 2.3 53 km SSE of Glacier View, Alaska
  5. 1.7 55 km SSE of Glacier View, Alaska
  6. 1.5 29 km WSW of Tatitlek, Alaska
  7. 1.5 27 km WNW of Tatitlek, Alaska
  8. 1.5 53 km WNW of Valdez, Alaska
  9. 1.5 55 km SSE of Glacier View, Alaska
  10. 1.7 39 km SE of Glacier View, Alaska
  11. 1.8 53 km SSE of Glacier View, Alaska
  12. 1.5 41 km WNW of Valdez, Alaska
  13. 1.6 57 km ENE of Whittier, Alaska
  14. 1.8 42 km W of Tatitlek, Alaska
  15. 1.6 50 km SSE of Glacier View, 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.