3.6

M3.6 Earthquake 68 km ENE of Adak, Alaska — November 18, 2020

2020-11-18 21:20:22 UTC (2020-11-18) · approx. 9:20 AM UTC-12 local

MagnitudeM3.6(mb)
Time21:20 UTC≈ 9:20 AM UTC-12
Depth156.2 kmintermediate depth
Coordinates52.135°, -175.727°
Felt byNo felt reports
Status✓ Reviewed by USGS

On November 18, 2020 at 21:20 UTC, a magnitude 3.6 intermediate depth earthquake struck 68 km ENE of Adak, Alaska, at a depth of 156.2 km and coordinates 52.1349°, -175.7266°.

Physical scale: An earthquake of magnitude 3.6 releases seismic energy equivalent to roughly 3.8 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 184 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 52.13°, -175.73°

Earthquake Details

Magnitude
3.6 mb
Depth
156.2 km
intermediate depth
Location
52.1349°N
-175.7266°E

Technical Information

Event ID
us6000cquw
Event Type
earthquake
Status
✓ Reviewed
Significance
199
Azimuthal Gap
134.0°
Min Station Distance
0.194°
RMS Residual
0.39 sec
Last Updated
2021-02-03 17:49:01 UTC

Common Questions

How strong was the magnitude 3.6 earthquake near Adak, Alaska?

The magnitude 3.6 earthquake that struck 68 km ENE of Adak, Alaska on November 18, 2020 at 21:20 UTC had a depth of 156.2 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 3.6 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 3.6 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: us6000cquw). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2020, November 18, 2020). M3.6 Earthquake 68 km ENE of Adak, Alaska — November 18, 2020. Retrieved February 3, 2021 from https://www.earthquaketracker.org/earthquakes/event/us6000cquw/