3.0

M3.0 Earthquake 26 km WSW of Trapper Creek, AlaskaSeptember 28, 2021

2021-09-28 20:57:45 UTC (2021-09-28) · approx. 10:57 AM UTC-10 local

MagnitudeM3.0(ml)
Time20:57 UTC10:57 AM UTC-10
Depth0.0 kmshallow crustal
Coordinates62.204°, -150.689°
Felt by2DYFI responses
StatusAutomatic (preliminary)

On September 28, 2021 at 20:57 UTC, a magnitude 3.0 shallow crustal earthquake struck 26 km WSW of Trapper Creek, Alaska, at a depth of 0.0 km and coordinates 62.2044°, -150.6890°.

Physical scale: An earthquake of magnitude 3.0 releases seismic energy equivalent to roughly 477 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 71 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 62.20°, -150.69°

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 2 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.

USGS DYFI community-reported intensity map for the M3.0 earthquake near 26 km WSW of Trapper Creek, Alaska

Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report

Earthquake Details

Magnitude
3.0 ml
Depth
0.0 km
shallow crustal
Location
62.2044°N
-150.6890°E
Felt Reports
2
DYFI responses
Community Intensity
2.0
CDI from reports

Technical Information

Event ID
ak021cgivzfe
Event Type
earthquake
Status
Automatic
Significance
139
RMS Residual
0.84 sec
Last Updated
2021-12-04 14:27:49 UTC

Common Questions

How strong was the magnitude 3.0 earthquake near Trapper Creek, Alaska?

The magnitude 3.0 earthquake that struck 26 km WSW of Trapper Creek, Alaska on September 28, 2021 at 20:57 UTC had a depth of 0.0 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 3.0 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 3.0 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: ak021cgivzfe). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2021, September 28, 2021). M3.0 Earthquake 26 km WSW of Trapper Creek, AlaskaSeptember 28, 2021. Retrieved December 4, 2021 from https://www.earthquaketracker.org/earthquakes/event/ak021cgivzfe/