A minor earthquake occurred Tuesday morning in southern Illinois.
The U-S Geological Survey reports the magnitude 2.1 temblor happened just before 10:00 am about four-miles southwest of Tamms. Preliminary earthquake data indicates the epicenter was located off of County Highway-4 along Sandusky Road in Alexander County.
The area is located in the Illinois Basin-Ozark dome Region. According to the USGS, earthquakes are moderately frequent in the region and occur at irregular intervals. The largest earthquake was a 5.4 reported in 1968. The Ozark Dome Region includes portions of Indiana, Kentucky, Illinois, Missouri and Arkansas.