Replies to This Discussion

Permalink Reply by Snake Stewart on September 13, 2008 at 4:32

Do you really think so ? Too nice to be that other guy.

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Permalink Reply by Snake Stewart on September 13, 2008 at 5:58

Now I am as lost as someone who just found out about the Haynesville Shale and wants to know how much their land is worth !

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Permalink Reply by Oil Neophyte on September 12, 2008 at 1:55

Spring Branch, ShaleGeologist or Les B:

You all appear to be knowledgable about the industry. I'm still trying to learn. Can any of you please explain what recoverable gas is and what a decline rate is? And can you explain it in such a manner that a dummy like myself can understand it? Any analogies or examples might be helpful.

I thank you for any information that you can provide.

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Permalink Reply by Les Bamburg on September 12, 2008 at 3:32

OIl Neophyte, there are no dummies just good people like yourself trying to gain a better understanding.

A formation or reservoir like the Haynesville Shale has a volume of gas originally in place before any production occurs. For example a company estimates one section (1 square mile) of the HS contains 170 billion cubic feet of gas (Bcf). It is not possible to recover or produce the entire volume of gas so some gas is left behind. The recoverable gas or reserves are the portion that can be actually produced. Initially the O&G companies estimate how much they believe can be recovered. So in our example the company estimated it could recover 51 Bcf or 30% of the total original gas in place. These estimates can be revised up (or down) as more information is gathered.

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Permalink Reply by Oil Neophyte on September 12, 2008 at 4:16

Les B:

Thank you for taking the time to explain this to me. What I don't understand is this. If a section has 170 BCF and can only get out 51 BCF, then there is 119 BCF left in the ground. That is a lot of money being left down there.

Shouldn't they be able to get out at least 50% of the 170 BCF in the ground? One would figure that the pressure would be enough to push out the gas until the pressure evened out. I guess i look at it like this. I'm siphoning out of one 5 gallon gas can into another. When the gas can that I am siphoning into reaches 2.5 gallons, I cannot siphon any more into it. Doesn't oil and gas production work the same way?

Also, you had previous posted about decline curves. Is pressure, or loss thereoff, the reason that you see such a decline in the first year of production (65% I think you said).

Thanks.

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Permalink Reply by RAY on September 12, 2008 at 5:56

its wise not to use real name on this site, but if it walks like a duck,etc..... then its the same ole Jim.
welcome back !

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Permalink Reply by BirdDawg, plain ole' idiot on September 12, 2008 at 14:37

Jim Krow,
I know i am a dumbass, but you just referred to "tight gas sands". This is shale. Permeabilty in a shale is basically nothing, as you well know. Just my opinion.

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Permalink Reply by BirdDawg, plain ole' idiot on September 12, 2008 at 14:53

Jim Krow (or whoever)),
Referring to your comment below mine., I knew you knew the deal, I just apparently missed your earlier post. Sorry. I know you know a lot about what you are talking about.

Permalink Reply by Les Bamburg on September 12, 2008 at 7:59

Oil Neophyte, as Jim K discusses the low porosity and permeability results in much lower recovery of the gas compared to traditional sandstone reservoirs. The 30% recovery level is probably conservative and I anticipate this number being higher (maybe as much as your 50%) as the companies learn more about the Haynesville Shale and develop better technology. Some gas is attached to the shale and is called the residual gas saturation. Continued high natural gas prices will definitely provide the incentive to maximize recovery.

There are several factors including loss of pressure that impact production decline. The initial production comes from the gas close to the fracture and does not have to travel far through the shale. As the well produces a longer period of time it is draining gas from a further distance from the fracture and has to travel through much more of the low permeability shale. There are others that are more knowledgeable than I on this topic.

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Permalink Reply by Oil Neophyte on September 12, 2008 at 8:13

O.K., you have all thoroughly confused me because I have no idea the difference between porosity and permiability.

What I still don't get is why can you only recover basically 1/3rd of the estimated gas in a section (51 bcf of 170 bcf). That means that there is still 2/3rds down in the ground. Why can't you get out at least 50%. Hasn't the oil industry by now built a huge Hoover Vaccum type machine that can just suck out the majority of the gas down there?

Like I previously posted, the O/G companies are leaving a lot of money down in the ground by extracting only about 1/3rd, more or less, of the gas that is down there.

Thanks for being patient with me and remember that I am a dummy when you reply, be sure use layman language.

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Permalink Reply by Bobi Carr ("parker") on September 12, 2008 at 8:39

Jim,

Thanks as usual for all of the helpful information that you bring to this site.

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Permalink Reply by Spring Branch,mineral owner on September 12, 2008 at 13:12

In layman's terms, porosity refers to the ability of the rock, lime, sandstone, etc to hold hydrocarbons. it is literally the pores in the rock. Permeability refers to the pores in the rock being connected to each other allowing the hydrocarbons to flow from one pore to the next, to the next, to the next and eventually to the well bore and up to the surface. Styrofoam would seem to be very porous, but because it lacks permeability, coffee cups don't leak.

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