1959 7.4 Quake Near Yellowstone Killed 28 People

In 1959, a large earthquake near Hebgen Lake caused the lake to “slosh” called seiches and triggered a major landslide that killed 28 people. The lake is located just outside Yellowstone Park. 

The 1959 Hebgen Lake earthquake^[2] also known as the 1959 Yellowstone earthquake^[2] occurred on August 17^[2] at 11:37 pm (MST)^[3] in southwestern Montana, United States. The earthquake measured 7.3 – 7.5^[4] on the Richter magnitude scale,^[5] and caused a huge landslide that caused over 28 fatalities and left US$11 million (equivalent to $90.37 million in 2016) in damage. The slide blocked the flow of the Madison River, resulting in the creation of Quake Lake. Significant effects of the earthquake were also felt in nearby Idaho and Wyoming, and lesser effects as far away as Puerto Rico and Hawaii.^[6]

^{https://en.wikipedia.org/wiki/1959_Hebgen_Lake_earthquake}

Credit to Wonder Hussy for doing an on the ground report and bringing it to my attention.

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