QuakeIndex

Earthquake · reviewed by a seismologist

M 3.7ml

Earthquake near Sterling, AK

No earthquake was likely felt in Sterling in the 24 hours to 12:19 pm AKST (21:19 UTC). The last one was M 2.5, 22 km (13 mi) NNE, at 9:11 pm AKST on 11 November 2026, estimated intensity II (weak) in town; 1 felt report to USGS. Every earthquake near Sterling

This page: a magnitude 3.7 earthquake was recorded 9 km (5 mi) south-southwest of Sterling, AK, at 4:51 am AKDT on 16 August 2023 (12:51 UTC), 58 km deep. 60 people have reported feeling it to USGS.

USGS: Kenai Peninsula, Alaska

98 km (61 mi) SSW of Anchorage, AK

4:51 am AKDT, Aug 16, 2023 · · 58 km deep · released about 5.4 tons of TNT

10 km30 km60 km120 km N Kenai Peninsula Borough 82 kmAnchorage Municipality 115 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
4:51 am AKDT on 16 August 2023 ()
Where
9 km (5 mi) south-southwest of Sterling, AK · earthquakes near Sterling
Magnitude
M 3.7 (ml)
Depth
58 km below the surface
Felt
60 reports · strongest reported intensity III
Measured shaking
intensity III (ShakeMap)
Nearest
Kenai Peninsula Borough, 82 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1113 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 49 km (30 mi) from the epicentre. In Sterling, 9 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.

Likely felt in: Sterling 9 km, intensity II · Soldotna 12 km, intensity II · Kenai 25 km, intensity II · Kalifornsky 25 km, intensity II · Nikiski 35 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 5.4 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.7 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 32,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 1,400× the energy of this one
  3. Magna, Utah 2020 M 5.7 1,000× the energy of this one
  4. This earthquake M 3.7 about 5.4 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 11× 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 4.7 on 2019-07-03 — about 32 times the energy of this one.

Before 2016, the USGS record lists 7 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.8 24 km ENE of Sterling, Alaska · 32 km NE of this epicentre
  2. 6.7 6 km WNW of Nikiski, Alaska · 41 km NW of this epicentre
  3. 6.4 19 km SSE of Tyonek, Alaska · 49 km NNW of this epicentre
  4. 6.0 31 km S of Funny River, Alaska · 29 km SSE of this epicentre
  5. 5.4 19 km NE of Nikiski, Alaska · 40 km NNW 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 60.4678, -150.8393. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Kenai Peninsula Borough, AK 82 km (51 mi) W earthquakes near Kenai Peninsula Borough
Anchorage Municipality, AK 115 km (72 mi) NE earthquakes near Anchorage Municipality

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. 2.4 10 km S of Funny River, Alaska
  2. 1.7 18 km SSE of Clam Gulch, Alaska
  3. 1.6 25 km SSE of Point Possession, Alaska
  4. 2.1 10 km S of Point Possession, Alaska
  5. 1.5 5 km NNE of Clam Gulch, Alaska
  6. 3.3 16 km SSE of Funny River, Alaska
  7. 3.4 20 km S of Funny River, Alaska
  8. 1.5 4 km NNW of Kalifornsky, Alaska
  9. 2.4 26 km ESE of Clam Gulch, Alaska
  10. 1.7 5 km NW of Nikiski, Alaska
  11. 1.7 5 km ENE of Kasilof, Alaska
  12. 1.7 Kenai Peninsula, Alaska
  13. 2.0 Kenai Peninsula, Alaska
  14. 3.1 10 km ESE of Nikiski, Alaska
  15. 1.5 19 km SSW of Point Possession, 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.