Like most North Dakotans, the citizens of Bismarck were accustomed to thunderstorms, blizzards, windstorms, and the occasional flood. But, today in 1968, they were to experience yet another of Earth’s natural threats: an earthquake.

At 11:52 AM on July 8th, the people of Bismarck were shocked as the capital city began to tremble. While the Bismarck Tribune reported that many residents attributed the tremor to nearby construction or an unstable building in which they were standing, the seismograph at the Colorado School of Mines reported that Bismarck was actually feeling the effects of shifting plates near Ashley, North Dakota, a small town 90 miles away.

In the center of North Dakota, a pre-cambrian, or bedrock, plate is divided into two sections. Due to pressure within the earth, one or both of the plates shifted, creating the quake. This quake measured a four on the Richter scale.

Residents reported only feeling the quake for a few seconds, but Colorado reported that the quake lasted about one and a half minutes. Though there were no damages due to the tremors, the people of Bismarck hoped this first reported earthquake in North Dakota history would also be the last.

by Tessa Sandstrom

Source: Bismarck Tribune. July 9, 1968: 1

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