Illinois vs Montana Earthquake Risk

Montana has a higher earthquake risk with a score of 6/10 (Moderate-High) compared to Illinois at 5/10 (Moderate). This means Montana faces more frequent and potentially more destructive seismic events.

Illinois averages approximately 30 earthquakes per year, while Montana averages about 150 per year. Montana experiences roughly 120 more earthquakes annually.

Illinois is associated with New Madrid, Wabash Valley seismic zones. Montana is associated with Intermountain Seismic Belt, Lewis & Clark zone. These fault systems determine the type and frequency of seismic activity each state experiences.

In Illinois, approximately 15% of the population lives in areas at risk from earthquakes, compared to 50% in Montana. Montana has a larger percentage of residents exposed to seismic hazard.

Illinois's most notable earthquake: 1968 Southern Illinois (M5.4). Montana's most notable earthquake: 1959 Hebgen Lake (M7.3). These historical events illustrate the seismic potential of each state.