M3.8 Earthquake 21 km NE of Granger, Wyoming — September 12, 2026
2026-09-12 05:25:49 UTC (34 min ago) · approx. 10:25 PM UTC-7 local
On September 12, 2026 at 05:25 UTC, a magnitude 3.8 shallow crustal earthquake struck 21 km NE of Granger, Wyoming, at a depth of 4.0 km and coordinates 41.7490°, -109.8087°.
Physical scale: An earthquake of magnitude 3.8 releases seismic energy equivalent to roughly 8.1 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 260 m — a useful intuition for the size of the slip patch on the fault.
ShakeMap — predicted shaking intensity
Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.
Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS
Earthquake Details
-109.8087°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 3.8 earthquake near Granger, Wyoming?
The magnitude 3.8 earthquake that struck 21 km NE of Granger, Wyoming on September 12, 2026 at 05:25 UTC had a depth of 4.0 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 3.8 earthquakes can continue for several days and gradually diminish over time.
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Understanding This Data
Magnitude 3.8 earthquakes are typically only recorded by instruments.
Authoritative source: USGS event page (event ID: uu80156391). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2026, September 12, 2026). M3.8 Earthquake 21 km NE of Granger, Wyoming — September 12, 2026. Retrieved September 12, 2026 from https://www.earthquaketracker.org/earthquakes/event/uu80156391/