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Oklahoma's Earthquakes Linked To Fracking
An anonymous reader writes Oklahoma has already experienced about 240 minor earthquakes this year, roughly double the rate at which California has had them. A recent study (abstract) has now tied those earthquakes to fracking. From the article: "Fracking itself doesn't seem to be causing many earthquakes at all. However, after the well is fracked, all that wastewater needs to be pumped back out and disposed of somewhere. Since it's often laced with chemicals and difficult to treat, companies will often pump the wastewater back underground into separate disposal wells. Wastewater injection comes with a catch, however: The process both pushes the crust in the region downward and increases pressure in cracks along the faults. That makes the faults more prone to slippages and earthquakes. ... More specifically, the researchers concluded that 89 wells were likely responsible for most of the seismic activity. And just four wells located southeast of Oklahoma City were likely responsible for about one-fifth of seismic activity in the state between 2008 and 2013."
That makes the faults more prone to slippages and earthquakes.
If my meager understanding of earthquakes is correct, these small slippages release in small bits the tectonic stress that could otherwise build up until a bigger quake happens. So, frack away?
This post contains no rudeness or derision of any kind. All arguments are friendly. Terms and exclusions may apply.
A majority of them are too small to be felt, but we have had 5.9's and 4.0's before. Even a 3.5 can easily be felt if the epicenter is close enough (of which, my house is only about 3-4 miles away from the epicenter of quite a few of them). The big deal is that it's starting to damage buildings. My house is developing a few cracks here and there, and some people are even getting serious enough as to having some foundational issues. When did it all start? When they started fracking. When did it stop? When they paused fracking for a while. When did it start up again? When they started fracking again. I know correlation does not equal causation but damn if that doesn't provide at least some necessitation to investigate.
They're nice enough to put their numbers and charts online. Which is great. https://cornell.app.box.com/okquakes/1/2137038978/18684174734/1
Unfortunately, their own charts show a bit of a problem. Specifically Figure S1.
The increase in earthquakes over time is definite. And it's NOT generally where the actual injection wells are. Sure, there's a few quakes recorded in the middle of the injection well area, but they're not consistent, and they don't map with time.
The earthquakes do map well with one thing, though: they seem to swarm around active seismic stations that aren't near fracking disposal wells. Which seems to either show that seismometers create earthquakes, or that they have some instrumentation issues.