3.3

M3.3 Earthquake 112 km E of Chignik, AlaskaAugust 11, 2024

2024-08-11 18:21:47 UTC (2024-08-11) · approx. 8:21 AM UTC-10 local

MagnitudeM3.3(ml)
Time18:21 UTC8:21 AM UTC-10
Depth67.0 kmshallow crustal
Coordinates56.503°, -156.614°
Felt byNo felt reports
Status✓ Reviewed by USGS

On August 11, 2024 at 18:21 UTC, a magnitude 3.3 shallow crustal earthquake struck 112 km E of Chignik, Alaska, at a depth of 67.0 km and coordinates 56.5028°, -156.6142°.

Physical scale: An earthquake of magnitude 3.3 releases seismic energy equivalent to roughly 1.3 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 114 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 56.50°, -156.61°

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 M3.3 earthquake near 112 km E of Chignik, Alaska

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

Earthquake Details

Magnitude
3.3 ml
Depth
67.0 km
shallow crustal
Location
56.5028°N
-156.6142°E
Intensity (MMI)
3.0
light

Technical Information

Event ID
ak024aar8573
Event Type
earthquake
Status
✓ Reviewed
Significance
168
RMS Residual
0.56 sec
Last Updated
2024-10-24 17:58:09 UTC

Common Questions

How strong was the magnitude 3.3 earthquake near Chignik, Alaska?

The magnitude 3.3 earthquake that struck 112 km E of Chignik, Alaska on August 11, 2024 at 18:21 UTC had a depth of 67.0 km. For context, this was a minor earthquake typically detected only by instruments.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.3 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 3.3 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: ak024aar8573). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2024, August 11, 2024). M3.3 Earthquake 112 km E of Chignik, AlaskaAugust 11, 2024. Retrieved October 24, 2024 from https://www.earthquaketracker.org/earthquakes/event/ak024aar8573/