Magnitude 3.8 Earthquake Shakes Ohlman, Illinois, Region

OHLMAN, IL. — A magnitude 3.8 earthquake struck near Ohlman, Illinois, in central Illinois early Tuesday morning, Jan. 20, 2026, according to the U.S. Geological Survey. The quake occurred at 1:27 a.m. Central Time about 3 miles north-northeast of Ohlman at a shallow depth of approximately 8.8 kilometers (5.5 miles), making it more noticeable despite its moderate size.

The tremor was felt across parts of Christian and Sangamon counties, including areas as far as the Metro East region and parts of St. Louis. The epicenter was located roughly 12 miles south-southeast of Taylorville, 33 miles south-southwest of Decatur, and 37 miles southeast of Springfield. As of early Tuesday, no injuries or property damage had been reported.

The Illinois Basin-Ozark Dome region, where the earthquake occurred, is known for moderately frequent seismic activity, although it is less active than the nearby New Madrid Seismic Zone. Earthquakes in this region typically happen at irregular intervals and can be felt over broad areas due to geological characteristics east of the Rocky Mountains. Historical records indicate that moderately damaging earthquakes happen every decade or two, with smaller tremors felt once or twice a year.

Geologists note that the region contains numerous faults within its bedrock, many of which are poorly mapped, making it difficult to link specific earthquakes to named faults. The best indicator of earthquake hazards in the area remains the seismic activity itself.

The largest recorded earthquake in the Illinois Basin - Ozark Dome region was a magnitude 5.4 event in 1968 that caused damage in southern Illinois. While the recent quake was smaller and caused no reported damage, it serves as a reminder of the ongoing seismic risks in central Illinois.

The 1811-1812 New Madrid earthquakes were a series of intense earthquakes with a 7.2-8.2 on Dec. 16, 1811, followed by a 7.4 aftershock on the same day. Two additional earthquakes of similar magnitude followed in January and February of 1812 on the New Madrid Fault.

Geologists note that the region contains numerous faults within its bedrock, but many are poorly mapped and it is difficult to link specific earthquakes to named faults. The best indicator of earthquake hazards in the area remains the seismic activity itself.