The Richter Scale measures earthquakes on a scale of one to ten. Earthquakes measuring two or less are common but so small they usually go unnoticed. The strength of an earthquake increases as it moves up the scale. An earthquake measuring five is considered moderate, while one approaching ten would be devastating, with widespread damage.
On this date in 2009, a rather unusual event occurred in North Dakota when residents in the Minot area felt the earth tremble. The earthquake measured 4.2. An earthquake of this magnitude is considered light to moderate and often goes virtually unnoticed.
When thinking of earthquakes, California immediately comes to mind. North Dakota does not. The state is one of the least seismically active areas in the United States. That doesn’t mean North Dakota is immune to earthquakes, but those that do occur are infrequent and generally not strong. There have been only thirteen recorded earthquakes in the state since 1900. California can have more than that in just 24 hours.
North Dakotans are not overly concerned about earthquakes because they are few and far between and are generally moderate when they do occur. For example, on Monday, July 8, 1968, the Capitol Building trembled a little. Some people reported that their coffee sloshed out of their cups and dishes rattled in cupboards. Most people, however, did not notice the movement at all. Those who did thought it might have been caused by a sonic boom. Very few people identified it as an earthquake.
North Dakota is located on one of the oldest and most stable sections of the earth’s crust. These regions lack the active dynamics found near major tectonic zones, like those in California. As a result, the risk of surface-rupturing earthquakes is statistically very low. Neighboring Montana, however, is located in a region of active faults. Montana’s strongest recorded earthquake, measuring 7.2, occurred in 1959.
So why don’t Montana earthquakes travel to North Dakota? Seismic waves lose intensity as they move through the earth’s crust. The distance between Montana’s active faults and North Dakota is great enough to act as a natural buffer. North Dakotans can be confident they are not on shaky ground.
Dakota Datebook written by Dr. Carole Butcher
Sources:
- Earthquake List. “North Dakota Earthquake List.” https://earthquakelist.org/usa/north-dakota/Accessed 7/15/2026
- Department of Mining Resources. “North Dakota Earthquake Catalog.” https://www.dmr.nd.gov/ndgs/documents/Publication_List/pdf/MiscSeries/MS-93.pdfAccessed 7/15/2026.
- North Dakota Mineral Resources. “Earthquakes in North Dakota?” https://www.dmr.nd.gov/dmr/ndgs/earthquakesAccessed 7/15/2026.
- Earth at Home. “Earth Hazards of Northwest Central United States.” https://earthathome.org/hoe/nwc/earth-hazards/Accessed 7/15/2026.
