What is fracking?

Learn how we can extract oil or gas from really firm rock.

Transcript:

Billy
Tell me about hydraulic fracturing, or fracking. It sounds like a pretty big deal.

Diego
It is. Fracking completely changed the whole energy picture. It unlocked huge amounts of natural gas and oil that were stuck deep underground, making the US a massive producer.

Billy
Okay. I get the impact, but I'm a bit fuzzy on the details. So, what exactly is it?

Diego
Well, hydraulic fracturing is basically a technique to get oil or gas out of rock that normally doesn't let anything through. Think of shale, it's really tight rock.

Billy
So how do you get anything out of it if it's tight?

Diego
That's the key. The whole idea is to blast a special fluid down there under huge pressure. This cracks the rock open so the trapped gas and oil can finally get out.

Billy
Wow, okay. So how do they actually do that? It sounds complicated.

Diego
It's kind of clever actually. First, they drill a well straight down, maybe a mile or even more. But then, once they get close to the rock layer they want, they turn the drill sideways and go horizontally for maybe thousands of feet.

Billy
Horizontally? Okay, I didn't know that. Then what? They just pump the fluid in?

Diego
Almost. After that, they punch little holes in the pipe that's way down there and then pump in the fracking fluid.

Billy
And what's in that fluid? Is it just water?

Diego
It's mostly water, yeah, plus some chemicals, and importantly, sand or similar stuff. They call it propants.

Billy
Propants? What's the sand for?

Diego
That's the most important part. The sand props open the cracks they just made even after they stop pumping. That lets the oil and gas flow back up to the surface.

Billy
So, if I've got this right, you drill down and sideways, use high-pressure fluid to crack the rock, and use sand to keep the cracks open so the fuel can get out.

Diego
Exactly. You've got it. Fracking is really about using that high-pressure fluid, the special horizontal drilling, and the sand to unlock fuel trapped way down in that tight rock.