M4.2 Earthquake 9 km N of Black Eagle, Montana — January 29, 2026
2026-01-29 19:41:09 UTC (2026-01-29) · approx. 12:41 PM UTC-7 local
Felt by 937 people across surrounding communities. Maximum shaking intensity MMI 4.3 (moderate).
On January 29, 2026 at 19:41 UTC, a magnitude 4.2 shallow crustal earthquake struck 9 km N of Black Eagle, Montana, at a depth of 23.5 km and coordinates 47.6105°, -111.2654°. The earthquake was reported felt by 937 peopleacross surrounding communities, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 4.3 (moderate). The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. This earthquake was detected by 87 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 693, making it a moderate-impact event. The nearest populated place is Malmstrom Air Force Base (population 3,472).
Physical scale: An earthquake of magnitude 4.2 releases seismic energy equivalent to roughly 30 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 476 m — a useful intuition for the size of the slip patch on the fault.
The epicenter is located in Montana, a region characterized by the Intermountain Seismic Belt, a diffuse zone of crustal deformation between the stable craton and the Basin and Range. View all earthquakes in Montana.
Learn more: Magnitude scale · Aftershock sequences
Nearest Populated Places
What the Shaking Felt Like
At MMI 4.3 (moderate), people in the most strongly affected areas would have experienced: Mild shaking, similar to a passing truck. Hanging objects swing. Glasses and dishes may rattle. Not commonly felt outdoors.
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
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 937 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
Population exposure (USGS PAGER)
Estimated population that experienced each level of shaking. Based on the USGS PAGER rapid impact assessment, which combines ShakeMap output with global population grids.
| Shaking intensity (MMI) | Description | Population exposed |
|---|---|---|
| MMI 3 | weak | 313,232 |
| MMI 4 | light | 95,795 |
Earthquake Details
-111.2654°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 4.2 earthquake near Black Eagle, Montana?
The magnitude 4.2 earthquake that struck 9 km N of Black Eagle, Montana on January 29, 2026 at 19:41 UTC had a depth of 23.5 km. It was felt by 937 people with maximum shaking intensity of MMI 4.3 (moderate). For context, this was a light earthquake commonly felt near the epicenter.
Where did the earthquake occur?
The earthquake epicenter was located at 47.6105°, -111.2654°, which is 9 km N of Black Eagle, Montana. The nearest populated place is Malmstrom Air Force Base (population 3,472). View all earthquakes in Montana.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.2 earthquakes can continue for several days and gradually diminish over time.
Has Montana had earthquakes this big before?
The largest recorded earthquake in Montana was the M7.3 Hebgen Lake earthquake of August 17, 1959. Today's magnitude 4.2 event is significantly smaller than that historical record.
What should I do after an earthquake?
If you were in the affected area: check yourself and others for injuries, inspect your home for damage, and be prepared for aftershocks. For detailed guidance, see our earthquake safety guide and emergency planning resources.
Authoritative source: USGS event page (event ID: us6000s5ba). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2026, January 29, 2026). M4.2 Earthquake 9 km N of Black Eagle, Montana — January 29, 2026. Retrieved May 19, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000s5ba/