USGS: Induced Earthquakes Raise Chances of Damaging Shaking in 2016

CNN:

The Oklahoma Corporation Commission is telling operators to shut down 35 disposal wells that may have played a role in a 5.6-magnitude earthquake that shook at least six states Saturday, Gov. Mary Fallin said.

Oklahoma was hit with a 5.6-magnitude earthquake two days ago. Tremors were felt in at least five neighboring states. It was one of the strongest earthquakes in Oklahoma history, equal in magnitude to the last record-setting quake, which hit south of Pawnee in November of 2011.

PBS reports “Oklahoma has seen an unprecedented surge in the number of quakes in the last five years. Before 2009, the state used to average only a handful of 3-magnitude or above earthquakes a year. But they have significantly increased every year after – reaching a peak of 900 in 2015.”

A News Hour report in January explains that in recent years “oil production has been on the rise in Oklahoma — partly due to technologies like fracking, a method of bursting rock formations to extract oil and gas. At some oil and gas wells, for every barrel of oil that’s produced, 20 barrels of salty wastewater bubble up as well.” In 2015, the report continued, “energy companies in Oklahoma injected 1.5 billion barrels of wastewater back into the earth” where the water “reduces friction between faults — or cracks — deep underground, releasing pent up energy and causing the earth to shake.”

A USGS report released in March confirmed that many earthquakes in the central United States are “triggered by human activities, with wastewater disposal being the primary cause for recent events.” Oklahoma Corporation Commission spokesperson Matt Skinner told CNN that “earthquakes in Oklahoma are generally not directly caused by fracking, but rather by pressure from the disposal wells, which are used by the industry to get rid of the toxic waste water that comes out of the earth along with oil and gas. The disposal wells dispose into the state's deepest formation, the Arbuckle formation, which is right above what we call the basement. The basement is above where the critical faults lie that shift and make earthquakes."

Wenonah Hauter, Executive Director of Food & Water Watch affirmed "this earthquake, and hundreds of others like it over the last few years, was the direct result of the underground disposal of fracking wastewater. There can’t be fracking without disposing of fracking waste, and there is no safe way to do so. This is just one of many reasons why fracking is inherently dangerous and must be banned.”