I've got a question. When a haynesville shale well has depleted its' production is it a done deal or does the shale characteristics allow for a "refracing" from the same well at a different angle or different depth? I have heard a lot about "porosity" and with shale not having the porosity of a sand formation I was wondering where it wasn't fraced if the gas would remain trapped. Any expert opinions on this would be greatly appreciated. Thanks and have a great day!

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Clay, some operators in the Barnett Shale have stated re-fracs are not economic and do not plan to re-frac. I am only aware of Devon refracing wells and many of those were done for vertical wells rather than horizontals.
les, I am basing all of my info off of what little time I was able to pick the brains of industry insiders and operators while I operating in the B - shale and I hope that I do not mislead anyone with outdated info.

Remember, a few years ago the Barnett was pretty much the only talked about unconventional Nat Gas play (not to say others had not been discovered or investigated), but at that time all eggs were in one basket. I am sure that in light of new production results in other plays operators have change their outlook on a formations future worth. I would assume the reason why Devon has only started re-stimulating the verticals is because they are the oldest wells. There will come a time when the horizontals will get their day in the sun, but I think that it is appealing for these companies to focus on high productivity in promising formations, like the H ville shale, and then turn around and figure new ways to maximize production out of lower producing formations, like the b shale. Les, you are correct by saying that it is not reasonable to re-frac a vertical B shale well, they are too low in pressure to begin with and there are not enough perfs in a vertical to get enough gas to maintain the integrity of the down-hole pressure and get the salt water off. This is why a large amount of well in the b shale are on gas-lift systems. Once again, I hope that my info is valuable and if anyone has any reason to believe that i am wrong, please call me on it so I can brush up on my info. Thanks.
Thanks Clay for your explanation and everyone else. If I understand you right Clay, you are saying based on Barnett history a 10mmfcd Haynesville well refraced could be expected to produce about 6.5mmfcd and could be refraced about 4 times in the life of the well. Do you are somebody else know what is the average lifespan of a Barnett well before it is refraced and is that what we can expect here?
Thanks Jim for the clarification, I was just wondering if a typical well runs 5 to 8 million to drill, how much does a refrac cost, and if after the refrac, it runs 65% of original production, wouldn't that make the economic feasability on these "triple x monsters" worth the cost?
Bruce, no operator in the Haynesville Shale has stated they can refrac a horizontal well 3-4 years later and have the production rate increase to 65% of original. Also, it is about how much incremental reserves you can recover due to the refrac. Example would be if the original well is projected to recover 6.5 Bcf and the refrac only adds another 1 Bcf.
Les,
Only another 1 BCF.
Thats six million dollars at 6 dollar gas. Sounds pretty good to me.
Whats the down side?
Thanks Les for the explanation, the figures I used I got from Clay in an earlier post in relation to the Barnett shale. The example you gave makes it crystal clear, thanks!
Clay you have stated there is not any horizontal refracing going on in the B-shale because of low gas pressure, porosity and other factors that the H-shale does not have such as the porosity is better here and the gas pressure is off the charts where a gas-lift station is not even needed. Knowing all of this, would the economic feasability of a refrac in the H-shale make it worthwhile?
Let me correct myself - I dont think that there is a whole lot of re-fracing in the Barnett because of the age of the production, it is not old enough. The Barnett still has allot of drilling to do, but when production starts to fall off I believe they will re-frac some horizontal Barnett wells. The low pressure and salt water in the Barnett make it less appealing. Your average b-shale well will come on at about 2 to 2.5 mmcf/day, while the H-shale comes on much stronger. Also, the flowing pressure of the H-shale is much stronger than the Barnett.

I really do not know too much about operating the H shale, but considering its production compared to the B shale I would believe it is feasible to re-frac it.
I've got a question for our resident experts. Please excuse my ignorance I am trying to go by memory on what I have heard. If the average thickness of the h-shale is approximately 500' and a frac on a horizontal well I have heard is done in 8 directions(described to me like a spider) when the frac is done, how many feet vertical and horizontal is fraced in the shale?
Bruce I hope you become correct on 500 feet being the average thickness of the HS. I wouldn't think the frac job goes out very far because the formation is so tight. I would think fracing tech will evolve to penetrate to greater distances as more is learned about the HS. I am kinda with Clay in a previous post, thinking that the HS may be a candidate for re-fracing at a later date when the tech may be better.
I'm trying to think of a single Haynesville Shale well that logged more that 300' and I can't come up with one. Can anybody out there help ? There may one day be a HS that logs 500'. but I can't imagine it being the average thickness. If it were the average, then I believe the avg. EUR's would be north of 8.5 B's.

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