4.7

M4.7 Earthquake 296 km SW of Adak, AlaskaApril 12, 2022

2022-04-12 09:15:09 UTC (2022-04-12) · approx. 9:15 PM UTC-12 local

Maximum shaking intensity MMI 4.9 (moderate).

MagnitudeM4.7(mwr)
Time09:15 UTC9:15 PM UTC-12
Depth10.0 kmshallow crustal
Coordinates50.184°, -179.909°
Felt byNo felt reports
Status✓ Reviewed by USGS

On April 12, 2022 at 09:15 UTC, a magnitude 4.7 shallow crustal earthquake struck 296 km SW of Adak, Alaska, at a depth of 10.0 km and coordinates 50.1843°, -179.9093°.

Physical scale: An earthquake of magnitude 4.7 releases seismic energy equivalent to roughly 169 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.1 km — a useful intuition for the size of the slip patch on the fault.

The epicenter is located in Alaska, a region characterized by Pacific Plate subduction beneath the North American Plate, producing frequent megathrust and crustal earthquakes along the Aleutian arc. The nearest mapped fault system is the Aleutian megathrust. View all earthquakes in Alaska.

Learn more: Magnitude scale · Aftershock sequences

Map showing earthquake epicenter at 50.18°, -179.91°

ShakeMap — predicted shaking intensity

Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.

USGS ShakeMap intensity contours for the M4.7 earthquake near 296 km SW of Adak, Alaska

Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS

Earthquake Details

Magnitude
4.7 mwr
Depth
10.0 km
shallow crustal
Location
50.1843°N
-179.9093°E
Intensity (MMI)
4.9
moderate

Technical Information

Event ID
us7000h1g1
Event Type
earthquake
Status
✓ Reviewed
Significance
340
Azimuthal Gap
51.0°
Min Station Distance
1.296°
RMS Residual
0.46 sec
Last Updated
2022-06-20 22:07:55 UTC

Common Questions

How strong was the magnitude 4.7 earthquake near Adak, Alaska?

The magnitude 4.7 earthquake that struck 296 km SW of Adak, Alaska on April 12, 2022 at 09:15 UTC had a depth of 10.0 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at 50.1843°, -179.9093°, which is 296 km SW of Adak, Alaska. View all earthquakes in Alaska.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.7 earthquakes can continue for several days and gradually diminish over time.

Has Alaska had earthquakes this big before?

The largest recorded earthquake in Alaska was the M9.2 Great Alaska earthquake of March 27, 1964. Today's magnitude 4.7 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us7000h1g1). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2022, April 12, 2022). M4.7 Earthquake 296 km SW of Adak, AlaskaApril 12, 2022. Retrieved June 20, 2022 from https://www.earthquaketracker.org/earthquakes/event/us7000h1g1/