Oklahoma is dealing with a significant increase in earthquakes near drilling sites, suggesting a link between hydraulic fracturing and seismic activity. Oklahoma has already experienced as many earthquakes this year to date than all of last year combined. There have been 109 earthquakes with a magnitude 3 or higher through April 6, the total number of earthquakes for all of 2013.
The incidents pose a conundrum for regulators in a state that has fully embraced oil and gas drilling. "We certainly likely have cases of earthquakes being caused by different oil and gas activity," Austin Holland, a seismologist with the Oklahoma Geological Survey, said in an interview with Bloomberg. "Evaluating those carefully can take significant amounts of time, especially when we're swamped." The state ordered the closure of two injection wells in Love County last year after several earthquakes occurred in the area.
Evidence of a link between earthquakes and fracking have cropped up in other places around the country before. Research on earthquakes in Ohio in particular has indicated a correlation. The research suggests that seismic activity is not necessarily linked to the fracking job, but to the injection wells where producers dispose of wastewater. In fact, research from the U.S. Geological Survey shows that fracking wastewater may have contributed to a six fold increase in earthquakes in the U.S. between 2000 and 2011.
The Oklahoma Oil and Gas Association denies the link, and says the jury is still out. "We're trying to make sure we understand what data the state needs in order to start making some determinations on cause and effect" said Chad Warmington, the trade association's President. "We don't want anybody to jump to conclusions." The group doesn't want Oklahoma regulators to halt drilling operations.