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Home » Special Events » Magnitude 3.8 earthquake in eastern Montana
last updated: 09/28/09 13:03.48 (PDT)
On Friday September 25 2009 at 8:11 AM (PDT) the USArray seismic network recorded an earthquake (preliminary ml 3.8) located in eastern Montana.
Initial source parameters for this tremor are indicated below. The epicentral distance (i.e. distance separating the epicenter and the closest station in the recording network, G24A) for the USArray is 38 km (0.34 degrees).
If you felt the quake, the USGS would like to know. Please add your comments to the USGS page "Did you feel it?".
Summary
| Solution Parameters | |
|---|---|
| Local Date: | Friday September 25, 2009 |
| Local Time: | 8:11 AM PST |
| Universal Time: | 09/25/09 (268) 15:11.34 UTC |
| Magnitude: | 3.8 ml |
| Latitude: | 45.0200 |
| Longitude: | -104.2100 |
| Depth: | 4 km |
| Author: | QED_weekly |
| Authoritative: | yes |
Proximity to Population Centers
- 48 km (30 miles) NE (39°) from Hulett, WY
- 48 km (30 miles) NW (324°) from Belle Fourche, SD
- 56 km (35 miles) NW (314°) from Fruitdale, SD
- 70 km (43 miles) N (11°) from Sundance, WY
- 501 km (311 miles) N (8°) from Fort Collins, CO
- 592 km (368 miles) N (6°) from Denver, CO
Maps
Mercator projection regional view
The red star denotes the earthquake epicenter. Triangle symbols are active stations at the time of the earthquake in the USArray (excluding ANSS backbone stations and GSN stations, which are represented by a diamond symbol) and colored by network. Gray lines are major rivers.
| Transportable Array (TA) | |
| UC San Diego (AZ) | |
| CalTech (CI) | |
| Uni. Utah (UU) | |
| ANSS backbone stations (US) | |
| Global Seismograph Network (IU) |
Regional satellite view
The red marker denotes the earthquake epicenter.
Detailed terrain view
The red marker denotes the earthquake epicenter.
Waveforms
You may view plots showing this event as recorded by USArray instruments:
- 3 components recorded by G24A, the closest USArray station to the event
- Large 3 components recorded by G24A, the closest USArray station to the event
- Vertical components from every eighth USArray station that recorded the event across the whole network
3 components recorded by G24A, the closest USArray station to the event:
News links
Search the internet
To search the internet for more information about this event, click on the button below:
Current seismic activity measured by USArray
Click the links below to observe near real time maps of earthquakes recorded by the USArray deployment:
Further information
Learn more about the Array Network Facility (ANF) component of USArray, the USArray experiment, the EarthScope project, and the Incorporated Research Institutions for Seismology (IRIS).
