There are no immediate reports of injuries.
Geophysicist Don Blakeman with the National Earthquake Information Center says the earthquake struck at 9:06 a.m with a preliminary magnitude of 4.5. The quake was centered about six miles east of Norman, where some minor damage such as broken windows has been reported.
Blakeman says the quake was felt as far away as Wichita, Kan.
Norman police Capt. Leonard Judy says the quake sent officers running out of the department to see if someone had crashed into the building.