Johnson County, IL has a moderate earthquake risk, with a total of 1 earthquakes since 1931. The USGS database shows that there is a 16.58% chance of a major earthquake within 50km of Johnson County, IL within the next 50 years. The largest earthquake within 30 miles of Johnson County, IL was a 4.2 Magnitude in 1994.
View the probability of a major earthquake within the next 50 years in Johnson County, IL.
View the number of earthquake incidents in Johnson County, IL by year that are more than 2.5 Magnitude.
Total Number of Earthquakes in Johnson County, IL within 30 miles. All distances and depths in the table are measured in miles.