Posted on 04/10/2008 11:30:14 AM PDT by reluctantwarrior
I have a question about this estimate. All the previous talk about 100 billion barrels of oil didn’t address what part of that was recoverable whereas this report specifically addresses that. So, what percentage did the USGS use in determining how much oil could be recovered? If it was 10% or so then there would be approx 43 billion barrels of oil there. Am I wrong in looking at it this way? Nothing was said in the report about how they arrived at their numbers.
I do not know.
I am also under the impression that the figure they gave was for undiscovered reserves (and an estimate), so at that point, the calculations they used elude me.
Completed well costs are closer to $7,000,000 right now. They should eventually come down to something around $5,000,000. The completion costs are nearly as much as the drilling costs because of the expensive frac jobs that the wells require to be able to produce.
Those numbers are the oil-in-place. The recovery factor should be about 10%.
It is actually a sandy dolomite.
No, there are two shales that are around 20' thick that are the source for the oil. Sandwiched between them is a sandy dolomite bed (also around 20' thick) that has all of the oil and gas in it. It is too thin and impermeable to make a commerical vertical well so horizontal wells are "sharpshooted" between the two shales to target the reservoir. Well costs currently are at $7,000,000.
Drilling thru the cheese to get to the ham
......
Something like that. The zone is productive over a large area where it can be considered marginally commercial. But what makes it profitable is finding the "sweet spots" where the rock has been fractured to increase in recovery.
Make your own! Drill vertically down to the middle of the layer, place explosive charges in the hole bottom, yell "Fire in the hole!" and run like hell!..............
Make your own! Drill vertically down to the middle of the layer, place explosive charges in the hole bottom, yell "Fire in the hole!" and run like hell!..............
That is essentially what the frac job does when they complete the well. In the old days, they used nitroglycerin but better technology has evolved.
One word: MOAB....................
Isn’t extremely high pressure mud pumping the current method?
No, there are two shales that are around 20’ thick that are the source for the oil. Sandwiched between them is a sandy dolomite bed (also around 20’ thick) that has all of the oil and gas in it. It is too thin and impermeable to make a commerical vertical well so horizontal wells are “sharpshooted” between the two shales to target the reservoir. To make the zone more permeable, the well is “fraced” with a mixture of gel and sand to prop the induced fractures open. Trucks at the surface pump into the well to cause these fractures. Well costs currently are at $7,000,000.
Thats what I meant by high pressure “mud” pumping but I’m not completely sure about the terminology. I was just suggesting that high explosives were not the current state of the art.
Mud is used in the drilling operation. When they frac the well, they use either “slick water” or gel. If you think about trying to carry sand in water, it would fall to the bottom so the gel makes the fluid viscous to be able to carry the sand into the fractures created by pumping into the borehole. When they stop pumping, the fracture tries to close but the sand grains keep it open.
Okay, I guess I had gotten the idea that “mud” was more of a generic term for thick-ish liquids used in various stages of the process. Got it now. Thanks
thanks I was cross posting some info from another site discussing general costs of horizontal drilling
the oildrum site posted yesterday
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