Oil Recovery May Have Triggered Texas Tremors 172
ananyo writes "First came reports of earthquakes caused by hydraulic fracturing and the reinjection of water during oil and gas operations. Now U.S. scientists are reporting tremors may have been caused by the injection of carbon dioxide during oil production. The evidence centers on a sudden burst of seismic activity around an old oil field in the Permian Basin in northwest Texas. From 2006 to 2011, after more than two decades without any earthquakes, seismometers in the region registered 38 tremors, including 18 larger quakes ranging from magnitude 3 to 4.4, scientists report in the Proceedings of the National Academy of Sciences. The tremors began just two years after injections of significant volumes of CO2 began at the site, in an effort to boost oil production. 'Although you can never prove that correlation is equal to causation, certainly the most plausible explanation is that [the tremors] are related to the gas injection,' says Cliff Frohlich, a seismologist at the University of Texas Institute for Geophysics in Austin, who co-authored the study."
Doesn't matter (Score:5, Insightful)
Had profit.
From TFA (Score:1, Insightful)
Until you figure out why CO2 injection causes problems at one oilfield, and not its neighbors, even though all of them have had similar amounts of CO2 injected, it seems rather more likely than not that the CO2 injection had nothing to do with the tremors.
OK, Got it. (Score:5, Insightful)
Although you can never prove that correlation is equal to causation... we're going to run with it because it works for us.
Got it.
But is this....bad? (Score:5, Insightful)
One thing I wonder as people talk about this. Now, I am no geologist but, my understanding of fault lines is that there are areas where tectonic plates cross, with one moving over the top of the other, pushing one down and one up. So far so good right?
So the model I have understood is, the fault compresses over time as the plates move, and then an earth quake happens when the stress is suddenly released, allowing the plates to slip some amount, relieving the stress and starting the process over again from its new position.
So now if this is an accurate enough description of the process, it seems to me like more frequent, smaller quakes are likely preferable to less frequent larger ones. So could this triggering of earth quakes actually be a....good thing? Is that question even being asked?
Re:From TFA (Score:5, Insightful)
Or that rocks will break and fracture in ways that aren't necessarily predictable.
It can be the cause in one well, and still not have caused the same problem in another well just simply by the local rocks and what's already happened to them.
I don't think anybody is suggesting "inject CO2, cause earthquake" ... but that the rocks might fracture (or whatever) in ways you don't really have a way to predict very well.
If it was pumping in the high pressure stuff that lead to unexpected mechanical failure of rock structures, you're never going to get a 100% result on something like that.
But I do think it highly likely there's more complexity going on than they're capable of knowing or controlling.
Comment removed (Score:5, Insightful)
Re:Doesn't matter (Score:5, Insightful)
You can bet a lot of people's insurance policies will be damaged one way or another...higher rates or no coverage for earthquake damage.
Re:Doesn't matter anyway. (Score:5, Insightful)
Given that fracking is a permanent change to the environment that can't be undone, EVER, I'd want to see some pretty compelling evidence that it absolutely can't cause harm, EVER, before being used widely across a bunch of different geologies.
Re:"Can never prove correlation is causation" (Score:4, Insightful)
I wasn't even concerned with the specific assertions in question. I just saw the "never" and my scientific absolutist alarms went off. Correlation is one of the most useful tools in the data collection toolbox, and to assert it has not intrinsic empirical value was bothersome to me.
It does need to be used responsibly, with controls and awareness of uncontrolled variables. It doesn't lack value for "proving" things. Certainly the summary and abstract didn't give sufficient detail about what might have been considered in this particular case.
Re:From TFA (Score:5, Insightful)
Until you figure out why CO2 injection causes problems at one oilfield, and not its neighbors, even though all of them have had similar amounts of CO2 injected, it seems rather more likely than not that the CO2 injection had nothing to do with the tremors.
And it couldn't be the Texas drought for the past three years... I mean what would drought have to do with land settling?
Re:From TFA (Score:4, Insightful)
Obliterates?
So this magically deals with all the pollution burning that stuff causes?
Tell us more.
Re:From TFA (Score:3, Insightful)
Don't let science get in the way of your ideology. I guess you're right, I'm a fan of clean air, clean water, and leaving things better than I found them, especially when it could affect a bunch of other people. I guess responsible energy production that thinks of more than just immediate need that makes me a dirty hippy.
Re:Doesn't matter anyway. (Score:2, Insightful)
Zero damage. This time.
But go back a few years.. The tsunami that hit india might have been caused by deep well injection a thousand miles away.
Lots n lots of damage that time.
And the bit about fracking is true. Safety is irrevelant. They ARE exempt from the EPA clean air and clean water acts. Pretty much nothing else in the world can claim that.
Re:seems like we have an identifiable pattern. (Score:3, Insightful)
The other way, where people never listen, is what happened with nuclear power, seat belts, electronics on planes, and vaccines:
1. New technology or idea proposed with significant internal research. It gets pushed hard by megacorps who see profit made in volume, but the technical research isn't widespread outside the industry.
2. Problems arise such as cancer, different injuries, slowly-developing illness, etc. Rumors and blame spread as the public is scared into believing anyone with any claim of expertise.
3. Industry reacts immediately to the concerns of regular citizens. Incidents due to operator error are reported to be 'isolated events' and media representatives are given the cold shoulder when their networks run stories spun to damage the industry.
4. Mounting evidence suggests new technology is just fine, but mounting anecdotes from "concerned citizens" continues to claim it's dangerous and has negative consequences.
5. Industry responds insisting everything is OK. Concerned citizens insist it isn't.
6. More evidence mounts, legislation gets proposed to curtail the technology and enact regulation, responding to public pressure.
7. Industry pushes back with their own research, while noting the gaps in what the research covers. Industry argues that regulation is not the answer because once enacted, regulation stops any further research into the issue, while wasting investment capital on certification costs.
8. Deaths, major accidents, and environmental impacts are being seen, but still can't be directly attributed to the new technology. Rumors and accusations still fly.
9. Industry starts pushing congressmen to ignore the panicking public. Congress, as usual, has already seen dozens of good panics in the last decade that didn't pan out, so this is unlikely to be different.
10. Industry no longer need to formally responds to complaints. Evidence against the technology consists solely of anecdotes and control-less studies crafted and spread to support the movement rather than the truth.
11. Industry pulls out after litigation expenses become threatening to the company, or simply accepts reduced profit until the unfounded controversy dies down and the technology is accepted as normal.
Re:Doesn't matter anyway. (Score:2, Insightful)
Given that fracking is a permanent change to the environment that can't be undone, EVER, I'd want to see some pretty compelling evidence that it absolutely can't cause harm, EVER, before being used widely across a bunch of different geologies.
Wasn't pumping any oil out in the first place a "permanent change that can't be undone ever"?
Or were you planning on recovering all the oil that had ever been pumped, and putting it back somehow?
Re:From TFA (Score:4, Insightful)
Until you can figure out why cigarettes causes lung cancer in on person, and not his neighbors who smoked similar amounts, it seems rather more likely that it wasn't the cigarettes that had anything to do with the cancer.
Frankly, I am not informed enough to have an opinion in this matter. However, even someone as ignorant in the matter as myself can see that your fact does not prove your conclusion. It doesn't prove that there is no link; it only proves that it isn't an absolute direct causation. It could mean that it affects probability and that different results were the luck of the draw. It could mean that there are other contributing factors (that we don't understand).
Re:From TFA (Score:4, Insightful)
Until you can figure out why cigarettes causes lung cancer in on person, and not his neighbors who smoked similar amounts, it seems rather more likely that it wasn't the cigarettes that had anything to do with the cancer.
Yes, that's absolutely correct. And then studies were done that showed significant statistical correlations between smoking and lung cancer. If it turns out that 80% of the areas where this was done have sudden increases in seismic activity, then there is probably a connection. A single data point is not enough to draw conclusions.
Re:From TFA (Score:5, Insightful)
Until you can figure out why cigarettes causes lung cancer in on person, and not his neighbors who smoked similar amounts, it seems rather more likely that it wasn't the cigarettes that had anything to do with the cancer.
Yes, that's absolutely correct. And then studies were done that showed significant statistical correlations between smoking and lung cancer. If it turns out that 80% of the areas where this was done have sudden increases in seismic activity, then there is probably a connection. A single data point is not enough to draw conclusions.
I would bet every penny I own that such a study would prove at least probable causation. I grew up in Oklahoma (bordering Texas) and for 30 years I never experienced an earthquake there, until 2009 when they started happening on a very regular basis. Coincidentally, most of the epicenters happened to be located near drilling operations.
Re:From TFA (Score:4, Insightful)
The pressures that they use to fracture rock are in the THOUSANDS of pounds, the pressures they're injecting CO2 at are in the HUNDREDS.
The CO2 isn't fracturing the rock.
Depends on how the rocks are sited and where the CO2 is injected. A pressure of "hundreds of pounds" doesn't guarantee that no rock crushing forces are generated. Bad luck could result in rocks being configured in such a way that when you injected the CO2, it pushed them together in such a way that unexpected movement occured.
If you inject 100psi of well contained CO2 under a large 50ft by 50ft slab of rock it's going to generate about 36 million pounds [google.com] force on that slab. In comparison, a 50ft cube of granite weighs around 21 million pounds [google.com]
Re:"Can never prove correlation is causation" (Score:4, Insightful)
What is more likely...
That earthquakes are just suddenly occurring where they previously never have and are occurring more frequently and violently where they normally have
Or...
That earthquakes, which we know are caused by instability in the Earth's crust, just might be result of recently punching massive holes and billions of fissures in the Earth's crust?