Six wastewater wells shut down in Oklahoma after 4.7 and 4.0 magnitude earthquakes rock state

Oklahoma oil and gas regulators shut down six drilling wastewater disposal wells on Thursday after the largest quake in the state since 2011 was recorded, Mike Soraghan reports for EnergyWire. Two wells were shut down around Cherokee (Best Places map) after a magnitude 4.7 earthquake, which was felt more than 300 miles away in Dallas and Kansas City, hit. Another earthquake, this one magnitude 4.0, was near Crescent, closer to Oklahoma City, leading to the closure of four wells.

"The Oklahoma Corporation Commission also directed the owners of 23 other wells around Cherokee to reduce injection by 25 to 50 percent," Soraghan writes. "Overall, the volume of wastewater injected by the 25 wells near Cherokee is to fall by 41 percent. Further reductions in volume are expected in the Crescent area, and other operators near Cherokee were told they may be directed to reduce operations. There were a total of eight earthquakes, with five in the Cherokee area and three in the Crescent area." No major injuries were reported.

Oklahoma, which in 2014 led the lower 48 states in earthquakes with 584 of magnitude 3 or higher, has already surpassed that total this year. Prior to the oil and gas boom of 2009, Oklahoma averaged two earthquakes of magnitude 3.0 or higher per year. (U.S. Geological Survey graphic)