Just before 4 a.m. on Thursday, the U.S. Geological Survey recorded a 4.0 magnitude earthquake.
The epicenter was located about three miles east of Carney.
The USGS also recorded a 3.3 magnitude earthquake just a few minutes later.
Just after 8:30 a.m. Friday, a 3.5 magnitude earthquake was recorded 2.5 miles southeast of Carney.
Another 2.7 magnitude earthquake was recorded 2.3 miles east-southeast of Carney just over an hour later.
The Oklahoma Corporation Commission, which regulates the oil and gas industry in the state, is sending inspectors to investigate 15 injection wells, according to spokesperson Matt Skinner.
“We’ve identified the wells that might be suspect and will audit them” for both the volume of wastewater they inject and the pressure used to inject the liquid, Skinner said.
The commission has previously directed oil and gas producers to close some injection wells and reduce volumes in others to lessen the chance of earthquakes.