MEDFORD, Okla. (AP) – An earthquake has shaken parts of northern Oklahoma.
The US Geological Survey says the 3.5 magnitude earthquake was recorded at 10:22 a.m. Thursday about four miles south-southwest of Medford in Grant County. The quake occurred at a depth of about one mile.
No injuries or damage was immediately reported. Geologists say damage is not likely in earthquakes below magnitude 4.0 and that earthquakes of magnitudes 2.5 to 3.0 are generally the smallest that are felt by humans.
Thousands of earthquakes have been recorded in Oklahoma in recent years. Many of the temblors have been linked to the underground injection of wastewater from oil and natural gas production operations.
State regulators have directed oil and gas producers to close some disposal wells or reduce the volume of fluids injected in others.