A small earthquake rattled parts of eastern Missouri and Western Illinois on Sunday night, though no damage or injuries were reported. The magnitude 2.0 quake struck at 8:23 p.m. just south of Valmeyer in Monroe County, south of St. Louis, along the northern edge of the Illinois Basin–Ozark Dome region. This area borders the more active New Madrid seismic zone.
According to seismic data, the earthquake occurred about 7 miles underground, with its epicenter located roughly 4 miles east-southeast of Herculaneum and 5 miles east-northeast of Festus.
Small earthquakes like this typically occur in the region once or twice a year. The strongest recorded earthquake in this area was a magnitude 5.4 event in 1968, which caused damage in Southern Illinois.