Could an operation related to hydraulic fracturing in West Virginia be responsible for more than half a dozen earthquakes that have hit the state’s southern Braxton County this year? According to a report from West Virginia Public Broadcasting, one state geologists says it’s possible.
This past April, Baxton County experienced a 3.4 magnitude earthquake. Since, then the area has been the site of at least six more, West Virginia Public Broadcasting said. Most were around a 2.7 magnitude – not enough to cause damage but enough for people to feel them.
State geologist and West Virginia Geological and Economic Survey Director, Michael Hohn told the network that the area is not known for seismic activity, and is generally “quiet.” So the upsurge in earthquake activity is both surprising and alarming.
According to West Virginia Public Broadcasting, a town in Braxton County called Frametown is home to holding tanks that store water used in hydraulic fracturing, or fracking, operations. The West Virginia Department of Environmental Protection has permitted Chesapeake Energy to use a nearby well to dispose of the drilling fluid. About ten million gallons of drilling fluid into the well since spring of 2009. Both the state and Chesapeake are trying to determine if the drilling fluid injections are releated to the recent earthquakes.
Meanwhile, the company is still using the well to dispose of water from Marcellus gas drilling. Local wells have also not been tested to see if the earthquakes have caused the disposal well to crack or leak fluid.
Hohn told West Virginia Public Broadcasting that normally static faults and fractures deep below the earth’s surface can move when liquid is injected underground. “It’s more than just lubricating the fault face, but it has a similar effect of essentially making it possible for the earthquake to take place, for the fault to move slightly,” he said.
Though Hohn characterized such earthquakes as “rare”, it’s likely happened before. For instance, a study released this past March of seismic activity in the Dallas/Fort Worth, Texas area found that the operation of a saltwater injection disposal well in the area was a “plausible cause” for the series of small earthquakes that occurred in the area between October 30, 2008, and May 16, 2009.
That study was conducted by researchers from SMU and UT-Austin/ The Dallas/Fort Worth quake started seven weeks after the disposal well there began operating in 2008 and stopped when the well was closed last summer.