"Great Shakeout" helps prepare Montanans for earthquakes

Earthquake Risk across the United States
Posted at 5:52 PM, Oct 20, 2022
and last updated 2022-10-20 19:55:11-04

On Thursday, October 20, 2022, schools and businesses across the nation participated in the "Great Shakeout” earthquake drill, including more than 10,000 participants around north-central Montana.

While Montana may not initially come to mind when it comes to earthquakes, the Treasure State is in one of the most seismically active regions in the United States.

The intermountain seismic belt, which runs through the western third of the state, is where the majority of the earthquake activity occurs in Montana.

The most notable earthquake in Montana’s history is the 7.3 magnitude Hebgen Lake earthquake on August 17th, 1959.

The earthquake triggered more than 160 new geysers throughout Yellowstone National Park. There were also around 28 fatalities from a rockslide in Madison Canyon.

And on July 6, 2017, one of the strongest earthquakes to hit Montana in decades shook the community of Lincoln, northwest of Helena. It was centered 5.5 miles southeast of Lincoln at a depth of about 2.6 miles

Helena has history of moderate earthquakes

People reported feeling the 5.8 magnitude quake across Montana and the northwest, with some reports coming from as far away as Vancouver and Lethbridge, Canada. It has caused some minor damage, but no fatalities or serious injuries.

The plains of central and eastern Montana are much less prone to quakes, but there have been a handful of significant ones reported.

According to the United States Geological Survey, a 5.3 magnitude earthquake struck northeastern Montana on May 15th, 1909. Several smaller quakes have been recorded in Roosevelt County, including an estimated 4.5 magnitude quake in the town of Froid that resulted in some damage to a grain bin back in 1943.

Although it has been some time since the state has seen a destructive earthquake, small quakes are estimated to occur several times every day. Click here to learn more about earthquake preparedness.