QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

Earthquake near Anchorage, AK

No earthquake was likely felt in Anchorage in the 24 hours to 10:36 pm AKST (07:36 UTC). The last one was M 3.5, 39 km (24 mi) SSW, at 4:48 pm AKDT on 27 October 2026, estimated intensity II (weak) in town; 98 felt reports to USGS. Every earthquake near Anchorage

This page: a magnitude 3.1 earthquake was recorded 20 km (12 mi) north of Anchorage, AK, at 6:10 am AKDT on 18 March 2019 (14:10 UTC), 40 km deep. 33 people have reported feeling it to USGS.

USGS: 8 km ENE of Point MacKenzie, Alaska

20 km (13 mi) N of Anchorage, AK

6:10 am AKDT, Mar 18, 2019 · · 40 km deep · released about 1,300 lb of TNT

Every earthquake near Anchorage Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Anchorage Municipality 39 kmMatanuska-Susitna Borough 98 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
6:10 am AKDT on 18 March 2019 ()
Where
20 km (12 mi) north of Anchorage, AK · earthquakes near Anchorage
Magnitude
M 3.1 (ml)
Depth
40 km below the surface
Felt
33 reports · strongest reported intensity III
Measured shaking
intensity II (ShakeMap)
Nearest
Anchorage Municipality, 39 km SE
Nearest mapped fault
Castle Mountain fault, 23 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2721 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 13 km (8 mi) from the epicentre. In Anchorage, 20 km away, the estimate is intensity II (weak). 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.

Earthquakes near other towns within 30 km: Big Lake, Eagle River, Knik-Fairview, Elmendorf Air Force Base, Houston, Meadow Lakes.

How big was it?

This earthquake released about 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 250,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,900× the energy of this one
  4. This earthquake M 3.1 about 1,300 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.4× 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 since 2016 was M 7.1 on 2018-11-30 — about 1,000,000 times the energy of this one.

Before 2016, the USGS record lists 20 earthquakes of M5 or more within 50 km; the five largest:

  1. 5.6 11 km NW of Big Lake, Alaska · 25 km NW of this epicentre
  2. 5.6 5 km N of Susitna, Alaska · 42 km WNW of this epicentre
  3. 5.5 2 km ENE of Eagle River, Alaska · 19 km ESE of this epicentre
  4. 5.5 9 km E of Susitna, Alaska · 31 km WNW of this epicentre
  5. 5.5 26 km SSW of Anchorage, Alaska · 46 km SSW 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 61.3966, -149.8432. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Anchorage Municipality, AK 39 km (24 mi) SE earthquakes near Anchorage Municipality
Matanuska-Susitna Borough, AK 98 km (61 mi) N earthquakes near Matanuska-Susitna Borough

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

Aftershocks so far

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

  1. 1.6 6 km NW of Point MacKenzie, Alaska
  2. 1.6 8 km NNW of Point MacKenzie, Alaska
  3. 2.2 5 km NNE of Point MacKenzie, Alaska
  4. 2.3 9 km E of Willow, Alaska
  5. 2.2 8 km SW of Big Lake, AK
  6. 1.6 5 km WNW of Point MacKenzie, Alaska
  7. 1.5 7 km NW of Point MacKenzie, Alaska
  8. 1.9 6 km SSE of Point MacKenzie, Alaska
  9. 1.6 4 km ESE of Point MacKenzie, Alaska
  10. 1.8 4 km SSW of Point MacKenzie, Alaska
  11. 1.9 16 km WSW of Willow, Alaska
  12. 1.5 3 km SE of Big Lake, Alaska
  13. 1.7 7 km ENE of Big Lake, Alaska
  14. 1.8 5 km W of Point MacKenzie, Alaska
  15. 1.5 5 km WNW of Point MacKenzie, 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.