I was just watching a documentary on natural gas wells and the insane amount of drilling going on and the contamination it's producing to the water and such. But in any case, I was googling and couldn't seem to find an answer on this. As everyone knows we pull so much oil and gas out of the ground everyday... with the amount me we pull out there must be huge oceans of the crap underground, at least my assumption.... What exactly happens when a well depletes? There has to be a hole underground? Does it ever cave in? I would think something must happen, that hole has got to fill in down there right? With the pictures they show even though its in spots here or there, they are extracting alot of liquid/gas out of the ground.. at some point something has to happen right? :bang:
They fill it up with water. http://www.popsci.com/holly-otterbe...ls-space-left-wells-when-oil-extracted-ground
Thank you dillinger. A bit awkward though, just water huh? I wonder what applies for the natural gas pockets... Personally I don't understand how the heck they get the oil up from the seabed, but they do it... it's sad we still rely on this junk.
Oil and stuff like that doesn't pool, it's not like a giant opening, think of it more like a sponge. It sits in the crevasses of rock. Water generally fills the remainder when you pump. When people say a oil well is "dry" it doesn't mean it's actually dry, it means that you're extracting more water than actual usable product.
Fracking is different. Fracking is a method of extracting more oil by increasing pressure on various areas of reservoir rock in order to form cracks/channels. So if we go back to the sponge analogy, think of it as creating a tunnel in the sponge in order to get the oil on one side to flow to the other. You do this because your pump is on the other side.
I worked in the field and have been on site both when wells are drilled and again when filled in (capped). An oil well may go 100% dry, but in most formations (layers of the earth's crust that have differing amounts of oil, natural gas, among other things) they never do go 100% dry. As was mentioned above, they fill in with water... salty water. In fact the majority of oil wells in the Midwest and Eastern US produce both oil, natural gas, and salt water (brine) which all needs to be separated and dealt with individually. When someone in the industry says "that well went dry" they likely mean that it reached the point where the ratio of water to oil was so bad that it wasn't wise financially to keep running it. There are various methods that can be used to try to increase that oil ratio again, but if nothing works or it's too expensive - the well will be capped with (allot) of concrete. *that's a vary abbreviated version, but that is usually the end result.
This is what happens when it all goes wrong. http://www.ksla.com/story/20329205/giant-louisiana-sinkhole-swallows-more-land
Yeah it just caves in but slowly, when the pressure of the gas pocket decreases, the earth fills up the hole, and then that earth over years based on what it is there, can develop also oil or coal or gas again
To answer your question. Whenever that happens to me I usually get a really rude stare from someone. Not my fault it has to deplete at some point in the day!
