Fracking, the practice of injecting water laced with noxious chemicals into shale and rock formations to loosen and liberate natural gas and oil that’s trapped between the layers, has long been suspected of causing earthquakes, among other ills.
Now a Dallas seismologist has become the latest to weigh in on such fears with the revelation that a recent series of small, unusual earthquakes in a suburb of the Texas city may well have been due to fracking, the colloquial name for hydraulic fracturing.
The first quake was a 3.4 magnitude on the Richter Scale, at 11:05 p.m. Central Daylight Time on September 30 a few miles southeast of Dallas–Fort Worth International Airport, and the second came four minutes later, a 3.1-magnitude aftershock in the same area, according to the U.S. Geological Survey (USGS). A day later, at 10:41 p.m. local time, a 2.1-magnitude temblor shook up residents, the website Life’s Little Mysteries reported.
Cliff Frohlich, associate director and senior research scientist at the Institute for Geophysics at the University of Texas at Austin, told Life’s Little Mysteries that it’s not a coincidence that since 2008, just after fracking began in the area, he found clusters of earthquakes originating within two miles of wastewater-disposal injection wells.
When fracking’s work is done, the leftover water is injected deep into the ground. In the case of Texas’s Barnett Shale formation, the water was shot thousands of feet below ground just south of the airport. Frohlich, analyzing data from 67 earthquakes that occurred between November 2009 and September 2011 in a 43.5-mile grid over the shale, found that many of them occurred in the vicinity of the wells. His theory is that the fluid lubricates tiny fault lines, making them movable.
He published his findings in August in the journal Proceedings of the National Academy of Sciences and reiterated his suspicions to Life’s Little Mysteries on October 2.
He is not the first to wonder whether fracking causes earthquakes. Fracking came under scrutiny last year relating to earthquakes in Oklahoma and Pennsylvania. With fracking battles heating up in New York state and New Brunswick, Canada, among other places on Turtle Island the question is becoming more and more pertinent.
Fracking has also been suspected, though never proven, to be responsible for groundwater contamination. However the recent detection of fracking chemicals in the groundwater of a town on the Wind River Indian Reservation in Wyoming may have put that assertion into question as well.