4.2

M4.2 Earthquake 223 km SE of Chignik, AlaskaMarch 26, 2022

2022-03-26 18:17:05 UTC (2022-03-26) · approx. 8:17 AM UTC-10 local

MagnitudeM4.2(mb)
Time18:17 UTC8:17 AM UTC-10
Depth11.4 kmshallow crustal
Coordinates54.758°, -156.129°
Felt byNo felt reports
Status✓ Reviewed by USGS

On March 26, 2022 at 18:17 UTC, a magnitude 4.2 shallow crustal earthquake struck 223 km SE of Chignik, Alaska, at a depth of 11.4 km and coordinates 54.7580°, -156.1286°.

Physical scale: An earthquake of magnitude 4.2 releases seismic energy equivalent to roughly 30 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 476 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 54.76°, -156.13°

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 M4.2 earthquake near 223 km SE of Chignik, Alaska

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

Earthquake Details

Magnitude
4.2 mb
Depth
11.4 km
shallow crustal
Location
54.7580°N
-156.1286°E
Intensity (MMI)
1.3
weak

Technical Information

Event ID
ak0223wvhy9y
Event Type
earthquake
Status
✓ Reviewed
Significance
271
RMS Residual
0.65 sec
Last Updated
2022-06-04 20:42:07 UTC

Common Questions

How strong was the magnitude 4.2 earthquake near Chignik, Alaska?

The magnitude 4.2 earthquake that struck 223 km SE of Chignik, Alaska on March 26, 2022 at 18:17 UTC had a depth of 11.4 km. For context, this was a light earthquake commonly felt near the epicenter.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.2 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 4.2 earthquakes are often felt but rarely cause damage.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: ak0223wvhy9y). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2022, March 26, 2022). M4.2 Earthquake 223 km SE of Chignik, AlaskaMarch 26, 2022. Retrieved June 4, 2022 from https://www.earthquaketracker.org/earthquakes/event/ak0223wvhy9y/