QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

Earthquake near Knik-Fairview, AK

No earthquake was likely felt in Knik-Fairview in the 24 hours to 11:40 am AKST (20:40 UTC). The last one was M 2.1, 7 km (4 mi) NW, at 8:17 am AKST on 11 November 2026, estimated intensity II (weak) in town; 1 felt report to USGS. Every earthquake near Knik-Fairview

This page: a magnitude 1.6 earthquake was recorded 2 km (2 mi) south-southwest of Knik-Fairview, AK, at 8:46 pm AKDT on 30 September 2019 (04:46 UTC), 31 km deep.

USGS: Southern Alaska

34 km (21 mi) NNE of Anchorage, AK

8:46 pm AKDT, Sep 30, 2019 · · 31 km deep · released about 7.6 lb of TNT

10 km30 km60 km120 km N Anchorage Municipality 40 kmMatanuska-Susitna Borough 86 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
8:46 pm AKDT on 30 September 2019 ()
Where
2 km (2 mi) south-southwest of Knik-Fairview, AK · earthquakes near Knik-Fairview
Magnitude
M 1.6 (ml)
Depth
31 km below the surface
Felt
no reports yet
Nearest
Anchorage Municipality, 40 km SSE
Nearest mapped fault
Castle Mountain fault, 16 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 2526 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Knik-Fairview, 2 km away, the estimate is intensity I (not felt). 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: Wasilla, Meadow Lakes, Tanaina, Big Lake, Houston, Eagle River.

How big was it?

This earthquake released about 7.6 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,400,000× the energy of this one
  3. Around the size people start to feel M 3.0 130× the energy of this one
  4. This earthquake M 1.6 about 7.6 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 7.1 on 2018-11-30 — about 180,000,000 times the energy of this one.

Before 2016, the USGS record lists 18 earthquakes of M5 or more within 50 km; the five largest:

  1. 5.9 23 km NE of Willow, Alaska · 47 km N of this epicentre
  2. 5.8 14 km NNE of Fishhook, Alaska · 49 km NNE of this epicentre
  3. 5.6 11 km NW of Big Lake, Alaska · 29 km WNW of this epicentre
  4. 5.6 5 km N of Susitna, Alaska · 49 km WNW of this epicentre
  5. 5.5 2 km ENE of Eagle River, Alaska · 19 km SSE 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 61.4922, -149.6175. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Anchorage Municipality, AK 40 km (25 mi) SSE earthquakes near Anchorage Municipality
Matanuska-Susitna Borough, AK 86 km (54 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

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

  1. 1.8 6 km W of Point MacKenzie, Alaska
  2. 2.4 6 km WNW of Point MacKenzie, Alaska
  3. 1.5 9 km SSE of Big Lake, Alaska
  4. 2.0 5 km NW of Point MacKenzie, Alaska
  5. 2.1 5 km N of Point MacKenzie, Alaska
  6. 1.7 1 km W of Point MacKenzie, Alaska
  7. 1.8 6 km WNW of Point MacKenzie, Alaska
  8. 1.7 2 km WNW of Point MacKenzie, Alaska
  9. 2.3 Southern Alaska
  10. 1.9 13 km NNE of Houston, Alaska
  11. 1.5 3 km S of Big Lake, Alaska
  12. 1.8 6 km WNW of Houston, Alaska
  13. 1.8 7 km NW of Elmendorf Air Force Base, Alaska
  14. 1.6 8 km NNE of Willow, Alaska
  15. 1.7 4 km SSE of Big Lake, 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.