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USGS · 70032705

The 16 May 1909 northern Great Plains earthquake

W. H. Bakun·M. C. Stickney·Gary C. Rogers
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Abstract

The largest historical earthquake in the northern Great Plains occurred on 16 May 1909. Our analysis of intensity assignments places the earthquake location (48.81° N, 105.38° W) close to the Montana–Saskatchewan border with an intensity magnitude MI of 5.3–5.4. Observations from two seismic observatories in Europe give an average Ms value of 5.3. The 1909 earthquake is near an alignment of epicenters of small earthquakes in Montana and Saskatchewan and on strike with the mapped Hinsdale fault in Montana. Thus, the 1909 earthquake may have occurred on a 300-km-long seismically active fault, which could have seismic-hazard implications for the region, particularly for the hydraulically emplaced earth-filled Fort Peck Dam, constructed in the 1930s on the Missouri River in northeast Montana.

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Bulletin of the Seismological Society of AmericaArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 28.16° to 54.13° latitude; -114.17° to -95.56° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeXRIS

W. H. Bakun, M. C. Stickney, Gary C. Rogers. 2011-12-08. The 16 May 1909 northern Great Plains earthquake. https://doi.org/10.1785/0120110054

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