New research indicates that wastewater disposal wells—and sometimes fracking itself—can induce earthquakes
Ohio regulators did something last month that had never been done before: they drew a tentative link between shale gas fracking and an increase in local earthquakes. As fracking has grown in the U.S., so have the number of earthquakes—there were more than 100 recorded quakes of magnitude 3.0 or larger each year between 2010 and 2013, compared to an average of 21 per year over the preceding three decades. That includes a sudden increase in seismic activity in usually calm states like Kansas, Oklahoma and Ohio—states that have also seen a rapid increase in oil and gas development. Shale gas and oil development is still growing rapidly—more than eightfold between 2007 and 2o12—but if fracking and drilling can lead to dangerous quakes, America’s homegrown energy revolution might be in for an early end.
But seismologists are only now beginning to grapple with the connection between oil and gas development and earthquakes. New research being presented at the annual meeting of the Seismological Society of America this week shows that wastewater disposal wells—deep holes drilled to hold hundreds of millions of gallons of fluid produced by oil and gas wells—may be changing the stress on existing faults, inducing earthquakes that wouldn’t have happened otherwise. Those quakes can occur tens of miles away from the wells themselves, further than scientists had previously believed. And they can be large as well—researchers have now linked two quakes in 2011 with a magnitude greater than 5.0 to wastewater wells.
“This demonstrates there is a significant hazard,” said Justin Rubinstein, a research geophysicist at the U.S. Geological Survey. “We need to address ongoing seismicity.” MORE