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In case you haven't heard, we humans use a lot of oil and gas these days; just a couple of sorts of hydrocarbons: organic compounds made out of hydrogen and carbon atoms. They are a magnificent source of stored energy, running a car engine, or a fighter jet, or a weed whacker, or power plant. Hydrocarbons are pretty useful.

A lot of the world's precious petroleum comes from the Middle East. That puts a lot of the world's countries in the position of having all of the useful oil and gas. So of course the rest of us are interested in hunting down some domestic sources.

And actually it turns out the Middle East doesn't have the hydrocarbon market cornered. They just have a lot more liquid petroleum than most places, but a lot of the rest of the world has reserves of natural gas. Gaseous hydrocarbons like methane and propane and butane usually found deep underground in giant beds of shale, a rock that was formed from the floors of ancient oceans.

Natural gas is likely how your water gets heated and maybe even your air. Burning it for electricity is cleaner and more efficient than coal, and unlike oil, when it spills it just vents into the atmosphere instead of spreading out in huge slicks over the ocean.

But the problem with natural gas has always been how do we get at it? We know it's there, but we can't get it. Well since the '40s, oil companies have known that breaking up the rocks in deep underground formations can increase the productivity of wells.

See it's not just one big pocket of black gold down there. Oil and gas can occur in thousands of little pockets and by fracturing the rocks around these pockets, the gas is released and can be collected. Usually this fracturing involves pumping millions of gallons of chemically treated water into deep shale formations. We're talking a mile or more underground at extremely high pressures. This fluid cracks the shale or widens existing cracks, freeing the hydrocarbons and making a path for them to flow toward the well.

So that's how it's done basically and some people are so unbelievably pumped about this technology, they're building little graven images to it and going to natural gas wells on Sunday mornings. But then, some scientists are like "not so fast you guys", cause fracking isn't all butterflies and cupcakes.

For starters, it uses a whole lot of water. It takes up to 7 million gallons to frack a single well and at least 30 percent of that water is trapped in the shale thousands of feet below the ground water aquifer, so it's gone for good.

And fracking fluid isn't just water. It's sand, which helps keep the cracks open once they're formed, and also chemical additives which can vary from well to well and they're often confidential. These additives do things like thicken the water to help suspend the sand or prevent mineral build-up in the pipe. And some of them are things you might find under your kitchen sink; others, like benzene and methanol, are pretty toxic.

Some concerns about the contents of these fracking fluids, not to mention radium, corrosive salts, and other stuff that comes back up from a mile underground, have led places like Pennsylvania to prohibit fracking outfits from sending their waste water to local treatment plants. And although fracking, when done correctly, shouldn't contaminate drinking water aquifers, that doesn't mean it hasn't happened. 

Subterranean systems are mysterious and it's impossible to tell how interconnected these shale deposits might be with groundwater. If the fracturing is too effective, groundwater aquifers and shale deposits containing newly injected fracking fluid can mix. Although it's hard to say how many cases of contamination have been caused by improperly installed or maintained fracking wells, improperly board or sealed wells have contaminated drinking water in several sites in the US, resulting in energy companies being fined for polluting water supplies.

While natural gas is a far cleaner fuel than coal, the fact that it doesn't spill and instead vents to the atmosphere, is also problematic for climate change. Methane is a potent greenhouse gas and if it isn't burned as it vents form fracking wells, it can contribute even more to global warming.

And finally, earthquakes. It's crazy but some US states like Oklahoma, Texas, and Colorado have been experiencing a significant rise in seismic activity, which seems to be corresponding to the fracking boom. Some studies are suggesting that the disposal of waste water back into used wells are causing the pressurized water to seep through cracks on the old fault lines, causing many more earthquakes than normal, even in places where seismic activity is rare.

So fracking; creating a new oil and gas boom in the US, sure, but it might not be all it's fracked up to be. Sorry, we didn't make any Battlestar Galactica jokes. So if you want you can put those down in the comments. 

And if you have any questions or comments or just want to argue about it, the comments are there for that as well. There's also sources, if you'd like to check those out. That would be good. And if you want to keep getting smarter with us here at scishow, you can go to youtube.com/scishow and subscribe.