By JORDAN GREEN, Editor-in-Chief
State officials ordered wastewater disposal wells in northern Oklahoma to cease operations or reduce the volume of wastewater they handle after a Friday earthquake rattled the region.
A 4.2-magnitude earthquake occurred at 7:56 a.m. Friday approximately 3.7 miles southwest of Manchester in Grant County, the U.S. Geological Survey reported.
The region is home to the Arbuckle rock formation.
Later that day, the Induced Seismicity Department of the Oklahoma Corporation Commission ordered wastewater disposal wells within 3 miles of the earthquake’s epicenter to cease operations. The agency told disposal wells within 3 to 10 miles of the epicenter to reduce by 50% the amount of wastewater they inject into the ground.
Wastewater disposal wells pump water used in oilfield processes into the ground.
“It is estimated that these actions will reduce disposed volumes by about 7,000 barrels a day,” corporation commission officials said in a news release. “Researchers are in broad agreement that disposal into the Arbuckle formation in parts of Oklahoma can raise risk of induced seismicity. Commission ISD directives since 2015 limiting or eliminating such disposal are among the actions credited with the sharp decrease in Oklahoma’s seismicity rate since 2015.”
The U.S. Geological Survey said Friday that the earthquake was one of the most significant earthquakes from around the world in the last 30 days.
Manchester is 48 miles northeast of Alva in Woods County and 55 miles northwest of Blackwell in Kay County.
No damage stemming from the quake was immediately reported by the survey office.
The Friday quake was reported at a depth of 7 kilometers, and it came after a series of quakes weeks earlier.