MEDFORD, Okla. (AP) — An earthquake centered near the northwestern Oklahoma city of Medford on Monday had a preliminary magnitude of 4.5, the U.S. Geological Survey reported.
The quake was 4 miles northwest of Medford, not far from the Kansas state line.
The threshold for damage usually starts at 4.0. Oklahoma’s strongest quake was a magnitude 5.8 recorded near Pawnee in 2016.
Many of the thousands of earthquakes in Oklahoma are due to the underground injection of wastewater from oil and natural gas extraction.
State regulators have directed producers to close or reduce volumes in some wells after quakes.
On Monday, the Oklahoma Corporation Commission ordered three wastewater disposal wells within 6 miles of the quake’s epicenter to shut down. Wells within 10 miles were ordered to restrict wastewater disposals to an average volume of 500 barrels a day.
