Earthquakes believed to be caused by oil well drilling and fracking operations caused earthquakes in the past several days in southern Oklahoma.
The strongest quake measured 3.7 magnitude near Duncan according to the U.S. Geological Survey. Its epicenter was located between Duncan and Velma-Alma in Stephens County. It was felt by residents around 7:40 p.m. on Sunday evening.
Dr. Jake Walter, State Seismologist with the Oklahoma Geological Survey (OGS) told the Norman Transcript, “We believe that those earthquakes are associated with hydraulic fracturing, which is going on right adjacent to that area. The operator actually paused operations as of Thursday, so there’s been no new injection going on into the subsurface since Thursday.”
He said the operator, Continental Resource, had since gone offline but there could also be a continuation of aftershocks.
“So this has continued, but we believe that it should taper off naturally throughout the next several days.”
The 3.7 quake was the strongest while others ranged from 2.3 magnitude to 3.0 magnitude. The quakes started on Tuesday, Sept. 19.