State officials are ordering the shutdown of some disposal wells after a 5.6 magnitude earthquake – one of the strongest ever recorded in Oklahoma – struck at 7:03 a.m. on September 3.
The quake, centered near Pawnee, shook structures in Tulsa and was felt as far away as Iowa, Missouri, Kansas, Texas, Arkansas and Nebraska. Several minor aftershocks were recorded in Pawnee.
More than 35 oil and gas wastewater disposal wells will be affected by the order.
The Oklahoma Corporation Commission issued this statement: “The Oklahoma Corporation Commission’s Oil and Gas Division (OGCD) is in the process of implementing a mandatory directive to shut down all Arbuckle disposal wells within a 725 square mile area, based on the location of the earthquake that occurred shortly after 7 a.m. on September 3 near Pawnee. The area includes 211 square miles of Osage County, which is outside of OGCD jurisdiction. OGCD is working with the Environmental Protection Agency, which has sole jurisdiction over disposal wells in Osage County. The EPA will determine what action to take in that area.”
Governor Mary Fallin declared a state of emergency for Pawnee County due to a magnitude 5.6 earthquake.
The earthquake was the strongest the state has experienced since November 2011 when a magnitude 5.6 earthquake occurred in Lincoln County.
“I’m glad to hear no one was seriously hurt in today’s earthquake and damage appears to be limited. This emergency declaration will start the process to helping individuals, families and businesses impacted by the earthquakes and serves as a precursor to requesting any necessary assistance,” said Fallin.
“I appreciate the quick response by the Department of Emergency Management and Department of Transportation to assess damage of the affected area and to ensure our state highway and turnpike bridges are safe.
“Information on the earthquake is still being collected and will be reviewed by my coordinating council on seismic activity chaired by Secretary of Energy and Environment Michael Teague, as we continue to move forward to make our state safe.”
Fallin’s executive order allows state agencies to make emergency purchases related to disaster relief and preparedness. The declaration also marks a first step toward seeking federal aid should it be necessary.
Under the executive order, the state of emergency lasts for 30 days. Additional counties may be added if needed.
Damage reports were not heavy but some older buildings in Pawnee were damaged and goods were knocked off shelves in some stores. At least a dozen homes were affected.
Seismologists cannot definitively say the cause of the earthquake. Oklahoma has had a spike in earthquakes with a magnitude of 3 or higher in recent years and the blame has been directed to wastewater disposal. But Oklahoma has had similarly sized earthquakes and the cause could be from the energy industry or the just the movement of tectonic plates.
The Oklahoma Geological Survey reported that it was “likely” that oil and gas wastewater wells were causing most of the earthquakes. The OGS does not blame hydraulic fracturing (fracking) for the problem.
Previously, the OCC announced a plan to decrease wastewater injection by 40 percent (compared to 2014). Kansas has a similar plan.
One report stated that there is a previously undiscovered fault line that could be 100 miles long in the same area.
Historically, Oklahoma has always had minor earthquakes with an average of only two per year of a 3 magnitude or higher.