M3.1 Earthquake 6 km ENE of Colstrip, Montana — November 19, 2021
2021-11-19 18:34:00 UTC (2021-11-19) · approx. 11:34 AM UTC-7 local
On November 19, 2021 at 18:34 UTC, a magnitude 3.1 shallow crustal earthquake struck 6 km ENE of Colstrip, Montana, at a depth of 0.0 km and coordinates 45.9059°, -106.5417°.
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.
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.
Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report
Earthquake Details
-106.5417°E
Technical Information
Common Questions
How strong was the magnitude 3.1 earthquake near Colstrip, Montana?
The magnitude 3.1 earthquake that struck 6 km ENE of Colstrip, Montana on November 19, 2021 at 18:34 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 3.1 earthquakes can continue for several days and gradually diminish over time.
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Understanding This Data
Magnitude 3.1 earthquakes are typically only recorded by instruments.
Authoritative source: USGS event page (event ID: us7000fvjg). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, November 19, 2021). M3.1 Earthquake 6 km ENE of Colstrip, Montana — November 19, 2021. Retrieved January 29, 2022 from https://www.earthquaketracker.org/earthquakes/event/us7000fvjg/