Another Earthquake Strikes Near Dallas-Fort Worth

Map courtesy of USGS

A map shows the location of the latest earthquake in the Barnett Shale drilling area.

Update: Read about the Dec. 12 quake outside of Fort Worth here. 

If you live around Dallas-Fort Worth, you may have noticed some shaking last night. No, it wasn’t Obama and Romney sparring over energy policy and the economy. It was another earthquake in an area that up until a few years ago had been seismically silent.

Around ten o’clock Tuesday night, a 2.7 magnitude earthquake struck near the town of Midlothian, Texas, according to the US Geological Survey. “It really shook our house too plus a loud boom,” one commenter on the website Texas Storm Chasers said.

Midlothian is part of the Barnett Shale, an area of drilling for natural gas. That natural gas is drilled by a process known as hydraulic fracturing, or “fracking,” where a mix of water, sand and chemicals is injected at high pressure deep underground to break up rock formations and release oil and natural gas. After a well is “fracked,” some of that liquid mixture comes back up. And it has to be disposed of.

Enter disposal wells. They’re essentially waste dumps that go even deeper underground, used to dispose of fracking liquids, and several scientific studies have made a definitive link between injecting fluids into these disposal wells and manmade earthquakes in the region (as well as other parts of the country).

It isn’t immediately clear if there’s any connection between this quake and disposal wells in the region. It can take months and even years to make such links scientifically, as we’ve reported earlier. But in the meantime you can read our earlier report: How Fracking Disposal Wells Are Causing Earthquakes in Dallas-Fort Worth