M2.1 Earthquake near Washington — October 11, 2020
2020-10-11 20:38:24 UTC (2020-10-11) · approx. 12:38 PM UTC-8 local
Felt by 11 people across nearby locations.
On October 11, 2020 at 20:38 UTC, a magnitude 2.1 shallow crustal earthquake struck near Washington, at a depth of 13.1 km and coordinates 47.6080°, -121.7325°. This earthquake was detected by 26 seismic stations with good location accuracy and was assigned a USGS significance rating of 70, placing it among routine seismic activity.
Physical scale: An earthquake of magnitude 2.1 releases seismic energy equivalent to roughly 19.9 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 16 m — a useful intuition for the size of the slip patch on the fault.
The epicenter is located in Washington, a region characterized by the Cascadia Subduction Zone, where the Juan de Fuca Plate subducts beneath North America and is capable of producing M9+ megathrust earthquakes. The nearest mapped fault system is the Cascadia Subduction Zone. View all earthquakes in Washington.
Learn more: Cascadia Subduction Zone · Magnitude scale · Aftershock sequences
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 11 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.
Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report
Earthquake Details
-121.7325°E
Technical Information
Common Questions
How strong was the magnitude 2.1 earthquake near Washington?
The magnitude 2.1 earthquake that struck near Washington on October 11, 2020 at 20:38 UTC had a depth of 13.1 km. For context, this was a minor earthquake typically detected only by instruments.
Where did the earthquake occur?
The earthquake epicenter was located at 47.6080°, -121.7325°, which is near Washington. View all earthquakes in Washington.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 2.1 earthquakes can continue for several days and gradually diminish over time.
Has Washington had earthquakes this big before?
The largest recorded earthquake in Washington was the M7.4 offshore earthquake of April 13, 1949. Today's magnitude 2.1 event is significantly smaller than that historical record.
Authoritative source: USGS event page (event ID: uw61682112). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2020, October 11, 2020). M2.1 Earthquake near Washington — October 11, 2020. Retrieved December 19, 2020 from https://www.earthquaketracker.org/earthquakes/event/uw61682112/