Study links Oklahoma earthquake swarm with fracking operations

From:  Los Angeles Times 

by Hailey Branson-Potts

Chad Devereaux of Sparks, Okla., examines damage to his in-laws' home after two earthquakes hit the area in less than 24 hours in 2011. A new study strengthens the link between Oklahoma quakes and fracking. (Sue Ogrocki / Associated Press)

 

Oklahoma has seen a boom in two things in recent years: oil and gas production and earthquakes.

To many residents, the timing says it all. Before the oil and gas industry started drilling so many underground injection wells, they say, it was rare to feel an earthquake. Today, Oklahoma is the second-most seismically active state in the continental United States, behind California.

Austin Holland, a seismologist at the Oklahoma Geological Survey, hangs up a chart depicting earthquake activity. He says a new study in the journal Science will help researchers understand the link between earthquakes and fracking. (Sue Ogrocki / Associated Press)

Now they have some fresh scientific evidence to back up their observations. Researchers from Cornell University and the University of Colorado say a large swarm of earthquakes in central Oklahoma was probably caused by activity at a few highly active disposal wells, where wastewater from drilling operations — including hydraulic fracturing — is forced into deep geological formations for storage.

Four high-rate disposal wells in southeast Oklahoma City probably induced a group of earthquakes known as the Jones swarm, which accounted for 20% of the seismicity in the central and eastern United States between 2008 and 2013, the team reported Thursday in the journal Science.  MORE