QuakeIndex

Earthquake · reviewed by a seismologist

M 4.7ml

72 km ENE of Pedro Bay, Alaska

Yes. A magnitude 4.7 earthquake was recorded 72 km ENE of Pedro Bay, Alaska, at 12:38 pm AKDT on 1 May 2016 (20:38 UTC), 130 km deep.

· 130 km deep · released about 170 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Kenai Peninsula Borough 47 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 4.7 (ml)
Depth
130 km below the surface
Felt
no reports yet
Measured shaking
intensity III (ShakeMap)
USGS impact alert
green
Tsunami
USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
Nearest
Kenai Peninsula Borough, 47 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1200 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.

At this magnitude and depth, people at rest would likely notice it out to about 93 km (58 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 170 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.7 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 1,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 45× the energy of this one
  3. Magna, Utah 2020 M 5.7 32× the energy of this one
  4. This earthquake M 4.7 about 170 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 350× 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

Tied for the largest within 50 km (31 mi) since 2016, with M 4.7 on 2016-01-24.

Before 2016, the USGS record lists 29 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.4 75 km WNW of Ninilchik, Alaska · 19 km N of this epicentre
  2. 6.4 52 km ENE of Pedro Bay, Alaska · 27 km SSW of this epicentre
  3. 6.2 70 km E of Port Alsworth, Alaska · 5 km NW of this epicentre
  4. 6.1 73 km WNW of Ninilchik, Alaska · 31 km NNE of this epicentre
  5. 6.0 53 km W of Anchor Point, Alaska · 36 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 60.1136, -152.9931. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Kenai Peninsula Borough, AK 47 km (29 mi) NE earthquakes near Kenai Peninsula 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. 1.8 49 km WNW of Happy Valley, Alaska
  2. 2.4 48 km E of Pedro Bay, Alaska
  3. 1.8 57 km WNW of Ninilchik, Alaska
  4. 2.6 62 km W of Anchor Point, Alaska
  5. 2.0 37 km ENE of Pedro Bay, Alaska
  6. 2.4 52 km E of Pedro Bay, Alaska
  7. 2.5 47 km E of Pedro Bay, Alaska
  8. 1.5 54 km NW of Ninilchik, Alaska
  9. 1.5 63 km E of Pedro Bay, Alaska
  10. 1.8 51 km E of Pedro Bay, Alaska
  11. 2.0 57 km E of Pedro Bay, Alaska
  12. 1.6 66 km W of Happy Valley, Alaska
  13. 2.0 60 km E of Pedro Bay, Alaska
  14. 1.6 60 km W of Happy Valley, Alaska
  15. 1.7 58 km E of Pedro Bay, 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.