6 January 2015
In the 1970s a tornado ripped roofs off the homes across the street while leaving our house untouched. Texas is one of those states prone to tornadic activity. They say a tornado sounds like a freight train. I could verify that except that I slept through the entire ordeal, damn it all. I remember one night, leaving my daughter’s place after dinner. The area was under a tornado watch, and the night was pitch black. Suddenly we heard the approaching sound of a freight train. I was about to experience my first tornado with my eyes open. The only thing is that in the darkness we couldn’t see which direction it was coming from, and that was pretty terrifying. Needless to say, when the headlight of a freight train suddenly emerged from the darkness, we were greatly relieved and felt more than a little silly.
I’ve always imagined that an earthquake would have a similar sound – a low rumble gradually growing in volume, becoming a roar which turns into a physical sensation. Likewise, the world would become an ever-increasing vibration, escalating in intensity until things starting falling off of shelves, cracks would race across walls and streets and then we’d all fall down. But my first experience with an earthquake was nothing like that. It started with an incredibly loud bang, as if said freight train had crashed into the building below my office window. This was followed immediately by a sound I’d liken to a 500-pound mad wearing clod-stompers running madly down the hallway outside my office. Simultaneously, there was the feeling that someone had grabbed the back of my chair, twisted it a quarter-turn counterclockwise and then wrenched it back before my brain could fully comprehend what had happened. And in less than 5 seconds it was all over. No time to climb under a desk or move into a door frame for protection. Not that protection was needed in this 3.5 mag quake. The girl in the next office experienced a similar twisting sensation, while the one in the next office down looked up as if someone was sledgehammering her ceiling. I was in the office until 9:30 pm and felt three additional tremors before leaving the office. All in all, through the morning of the following day, the area experienced 10 separate events.
There is a great debate in north Texas about the effects of hydraulic fracturing, known popularly (or unpopularly, depending on your views) as ‘fracking.’ Fracking is a well stimulation technique in which rock is fractured by a hydraulically-pressurized liquid. A high-pressure fluid (usually chemicals and sand suspended in water) is briefly injected into a wellbore to create cracks in the deep-rock formations through which natural gas, petroleum, and brine will flow more freely. When the hydraulic pressure is removed from the well, small grains of hydraulic fracturing proppants (either sand or aluminum oxide) hold the fractures open once the deep rock achieves geologic equilibrium.
Fracking is very controversial. Proponents advocate the economic benefits of more extensively accessible hydrocarbons. But the environmental impact includes contamination of ground water, depletion of fresh water, degradation of air quality, noise pollution, surface pollution and the consequential risks to health and environment. Also among the potential consequenses is the triggering of earthquakes. Increases in seismic activity following fracking along dormant or previously unknown faults are sometimes caused by the deep-injection disposal of hydraulic fracturing flowback (a byproduct of hydraulically fractured wells), and produced formation brine (a byproduct of both fractured and nonfractured oil and gas wells). For these reasons, hydraulic fracturing is under international scrutiny.
Seismologists from SMU’s Huffington Department of Earth Sciences in Dedman College are investigating the earthquake sequences in north Texas. But as a buddy of mine says, “I’ve lived here all my life and this shit never happened when we were growin’ up.” What more evidence do you need than that?