3.1

M3.1 Earthquake 219 km WSW of Adak, AlaskaJuly 8, 2023

2023-07-08 18:05:16 UTC (2023-07-08) · approx. 6:05 AM UTC-12 local

MagnitudeM3.1(ml)
Time18:05 UTC6:05 AM UTC-12
Depth63.8 kmshallow crustal
Coordinates51.510°, -179.760°
Felt byNo felt reports
Status✓ Reviewed by USGS

On July 8, 2023 at 18:05 UTC, a magnitude 3.1 shallow crustal earthquake struck 219 km WSW of Adak, Alaska, at a depth of 63.8 km and coordinates 51.5100°, -179.7597°.

Physical scale: An earthquake of magnitude 3.1 releases seismic energy equivalent to roughly 674 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 83 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 51.51°, -179.76°

Earthquake Details

Magnitude
3.1 ml
Depth
63.8 km
shallow crustal
Location
51.5100°N
-179.7597°E

Technical Information

Event ID
us7000kftl
Event Type
earthquake
Status
✓ Reviewed
Significance
148
Stations Used
23
Azimuthal Gap
177.0°
Min Station Distance
0.527°
RMS Residual
0.34 sec
Last Updated
2023-09-09 21:55:21 UTC

Common Questions

How strong was the magnitude 3.1 earthquake near Adak, Alaska?

The magnitude 3.1 earthquake that struck 219 km WSW of Adak, Alaska on July 8, 2023 at 18:05 UTC had a depth of 63.8 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 3.1 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 3.1 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: us7000kftl). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, July 8, 2023). M3.1 Earthquake 219 km WSW of Adak, AlaskaJuly 8, 2023. Retrieved September 9, 2023 from https://www.earthquaketracker.org/earthquakes/event/us7000kftl/