Earthquakes, including one 4.2 magnitude, in north Oklahoma
ENID, Okla. (AP) — The Oklahoma Geological Survey recorded several earthquakes Friday in the northern part of the state, including ones of magnitude 4.2, 3.7 and 3.5.
The quakes were recorded southeast of Enid, about 95 miles (150 kilometers) north of Oklahoma City.
No injuries or damage were reported, according to Garfield County Emergency Management Director Mike Honigsberg. Geologists say damage is unlikely from temblors below magnitude 4.0.
Thousands of earthquakes have been recorded in Oklahoma in recent years, many linked to the underground injection of wastewater from oil and gas production, which is being considered as a cause of the tremors, said state seismologist Jake Walter.
“This is an area we were already examining. We’ve also observed some smaller seismicity in the past month, not perceptible to humans,” Walter said. “It’s likely that it’s wastewater disposal related.”
There are about a dozen active disposal wells within a 10 mile radius of the earthquakes, said Oklahoma Corporation Commission spokesperson Sarah Terry-Cobo.
In response to the quakes, commission regulators ordered oil and gas operators to cease disposing of wastewater within three miles of the earthquake’s epicenter and to reduce disposal volume within three to 10 miles of the epicenter. The commission estimates the actions will reduce disposal volume by about 9,000 barrels each day.
The 4.2 magnitude quake was recorded about 11:45 a.m., about 90 minutes after the magnitude 3.7 and 3.5 quakes, in addition to at least six other tremors ranging from 2.0 to 2.7 magnitude.