M3.3 Earthquake 39 km SSE of Mammoth, Wyoming — July 16, 2026
2026-07-16 13:20:11 UTC (2026-07-16) · approx. 6:20 AM UTC-7 local
Felt by 26 people across nearby locations.
On July 16, 2026 at 13:20 UTC, a magnitude 3.3 shallow crustal earthquake struck 39 km SSE of Mammoth, Wyoming, at a depth of 6.5 km and coordinates 44.6665°, -110.4675°. This earthquake was detected by 33 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 180, placing it among routine seismic activity.
Physical scale: An earthquake of magnitude 3.3 releases seismic energy equivalent to roughly 1.5 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 120 m — a useful intuition for the size of the slip patch on the fault.
The epicenter is located in Wyoming, a region characterized by the Yellowstone volcanic system and Teton Fault, where a mantle plume drives volcanic seismicity and crustal extension. The nearest mapped fault system is the Teton Fault. View all earthquakes in Wyoming.
Learn more: Magnitude scale · Aftershock sequences
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 26 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
-110.4675°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 3.3 earthquake near Mammoth, Wyoming?
The magnitude 3.3 earthquake that struck 39 km SSE of Mammoth, Wyoming on July 16, 2026 at 13:20 UTC had a depth of 6.5 km. For context, this was a minor earthquake typically detected only by instruments.
Where did the earthquake occur?
The earthquake epicenter was located at 44.6665°, -110.4675°, which is 39 km SSE of Mammoth, Wyoming. View all earthquakes in Wyoming.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.3 earthquakes can continue for several days and gradually diminish over time.
Has Wyoming had earthquakes this big before?
The largest recorded earthquake in Wyoming was the M6.5 Yellowstone Lake earthquake of June 30, 1975. Today's magnitude 3.3 event is significantly smaller than that historical record.
Authoritative source: USGS event page (event ID: uu80145411). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2026, July 16, 2026). M3.3 Earthquake 39 km SSE of Mammoth, Wyoming — July 16, 2026. Retrieved July 23, 2026 from https://www.earthquaketracker.org/earthquakes/event/uu80145411/