What is causing all the recent Edmond earthquakes?
EDMOND — Ground shakes being felt here most likely are leftovers from strong earthquakes that happened in January, Oklahoma's state seismologist says.
On Jan. 12, a trio of earthquakes happened with magnitude ratings of 3.2, 4.3 and 2.5. Early the next day in the same general area, a 2.6 magnitude earthquake was recorded, followed by a 4.1 and another registering 2.7 on the Richter scale.
Data obtained Friday showed the Oklahoma Geological Survey has recorded 17 earthquakes, generally around Danforth Road's intersection with I-35, over the past 30 days.
Are oil and gas activities to blame for the recent earthquakes near Edmond?
The relation to oil and gas drilling in the area is being studied.
But Oklahoma's Corporation Commission began restricting oil and gas wastewater disposal into the Arbuckle, a geological formation underlying most of the state as deep as 30,000 feet, about 10 years ago after research identified that practice as a potential source of induced earthquakes.
By 2017, all Arbuckle disposal wells in the Edmond area had ceased operating. No new Arbuckle wells have been drilled in that area since 2015, agency officials say.
More: State orders more oil and gas wastewater disposal wells shut after latest Prague earthquakes
In late 2016, hydraulic fracturing also was identified as a potential source for smaller, more localized earthquakes across the state. There has been no hydraulic fracturing in Edmond this year, they say.
"The activity in the area remains under study by the Oklahoma Geological Survey and the Oklahoma Corporation Commission's Induced Seismicity Department," said Matt Skinner, the agency's regulatory program/public information manager.
Only some of Edmond's shaking is being felt by residents, Oklahoma's seismologist says
Jake Walter, Oklahoma's state seismologist, said more than 150 aftershocks — most too small to be felt by people — have been recorded in northeast Edmond since January, an area seismically active since about 2014 when several strong earthquakes were centered there.
"It has just been a particularly active small fault zone that sometimes produces magnitude 4.0 earthquakes," Walter said. "These faults are inherently unstable.
"We should expect aftershocks for the next several months," Walter said.
This article originally appeared on Oklahoman: Edmond OK earthquakes likely aftershocks from stronger January events
