Giant Straw to Suck up East Branch

[JeffK]

Back to flooding, the people in Phillipsburg and Trenton, NJ and Easton, PA (along with others) worry a lot about flooding. They don't care about natural gas drilling or NYC's water supply since that is not in their back yard. However, they have been complaining about flooding and more pressure from NJ and PA will concern flooding.

 

[Dr. Gonzo]

Think of it kinda like a submerged stack of wood. If one was able to lift the stack of wood out of the water, the water that was in the spaces between each piece of wood would drain out, but the stack of wood would still be standing.

I have yet to see anything that would indicate that drilling causes geological instability, but the analogy you're using to explain what happens to the shale in inapt. In hydraulic fracturing you're using pressurized water and chemicals to break apart the shale to get the gas out. So it's more like smashing the wood pile flat to squeeze out that water that is in between the wood grains.

 

[Future Fanatic]

I have yet to see anything that would indicate that drilling causes geological instability, but the analogy you're using to explain what happens to the shale in inapt. In hydraulic fracturing you're using pressurized water and chemicals to break apart the shale to get the gas out. So it's more like smashing the wood pile flat to squeeze out that water that is in between the wood grains.

To suggest that the rock formation is pulverized so as to be squeezed flat is inept.

NOW MAYBE it would be better to say that if I cut down a tree, chunked it and stacked the rounds, that the splitting of the wood (without moving the stack)is like the fracturing process. The splitting of the wood allows the moisture to escape the wood more quickly. I still have a stack of wood.

Ya just can't take the analogy for what it is, can ya... SO,

There are spaces in between the particles within the shale. There are MANY spaces between the particles. The problem is that these spaces(unlike a stack of wood) are not very well connected to eachother. It's not like a sponge where you could pour water in at the top and have it drip out the bottom. It's more like a block of glass with lots of air bubbles trapped in it. Anyway, these spaces are where the bulk of the highly pressurized gas is trapped. The Marcellus Shale does have some "faulting" and horizontal drilling through the shale layer exposes more of the bore hole to these channels through the formation. BUT, in order to reach as many of these channels as well as expose as much of the rock to the relative lower pressure of the bore hole, they fracture the rock. Into these fractures, they force varying sizes of sand to prop open the fractures when the pressure is released. These propped open fractures allow much of the trapped gas in the "pores" of the rock to escape over time. It may be five years or twenty five years.

It's not as if the layer of rock turns to dust, falls to the bottom of the "new cave" while the gas sits at the top to be sucked out with a straw.

AND I wonder, since they are pressurizing the layer, creating cracks(spaces)and then forcing sand in to prop them open, if the layer is then actually thicker when they are done. My stack of split wood is always taller than my stack of cut rounds...

 

[babyblue]

Yes, but, The stack of cut round is smaller in volume than the stack of cut split, ya follow?

 

[Future Fanatic]

Yes, but, The stack of cut round is smaller in volume than the stack of cut split, ya follow?

Yes, same amount of wood, smaller amount of space.

Or do you mean by "smaller volume" that it is harder to hear?

 

[babyblue]

John,
I hear fine, seeing is the problem, remember!

 

[Kilgour Farms]

Heres info on shale gas formation and extraction from Canadian center for energy.

Centre for Energy™ : Centre For Energy