Welcome to Petroleum Geology Forums

Trying things such as you suggest might help. However, the creep problem begins when the cased hole logs are "tied" into the open hole logs. The cased hole logs (corelation logs) are pulled at some rate of speed that is required by the tools involved. After this correlation log is run, the perforating gun is run with a collar locator and tied into the casing collars recorded by the correlation log, generally, at about the same speed that was used for the correlation logs .There is stretch in the line when these "tie" in runs are made. There are many contributors to creep. Just because the perforating gun is pulled slowly, after tieing into the casing collars, does not eliminate the stretch that was in the line when the tools were tied into the casing collars. This will then result in the perforating gun being in the wrong position (too high) when the gun is fired. When I study problem wells, one of the questions I ask myself is, "what would the production from this well look like if the perforations are 5', or 10', or 20' higher than we think they are." I have found that the deeper the well, the heavier the gun, the bigger the OD of the fun, the greater creep will be. Thus far, I have seen creep be 30' in a well that was 16,500' deep. That was a straight hole. Add hole deviations, dog-legs, etc. into the picture, and creep gets worse.

I am so sure that creep is a major problem that is being ignored by the industry, I am willing to make this offer: if your company will provide transportation and cover all expenses, I am willing to supervise, AT NO CHARGE FOR MY TIME, the perforating of a deep well with a casing gun on wireline. I will provide the necessary proof of the amount of creep and how far off depth the perforations would have been if creep had not been determined. Please let me know if you and your company are interested.

I suggest that your perforating companies be contacted and asked what they know about creep and how they compensate for it when perforating. WARNING: do not be surprised if they do not know about creep or even that it exists. I will be greatly surprised if they know how to find creep and compensate for it. Please post your findings about this issue.

I am also willing to work with the perforating companies to ensure that this problem is solved.

I am finding this very interesting. I am currently in a class in Bangkok with two ex-Schlumberger wireline engineers, both are now working for Chevron. Neither one of the knew anything about wireline creep and had no idea how to find it.

That is worrying news indeed. I would expect with all the technology available and R&D done whithin the industry a thing like this would be well looked after. It seems like a "mistake" that is very likely to occur in many operations, judging from your description and the fact that it is only looked into now (afters decades of drilling history) is quite worrying...

...but also illustrates how the industry can still evolve and that we still not fully grasp every aspect of what we do in the oil and gas industry. That's what I love about it!

I am interested in purchasing wells that I believe to have this creep problem. If your company has a person or department that sells poorly producing wells, or wells being held for abandonment, please provide the contact information. Thanks.

I just returned from the Oklahoma Oil Show. Attending was a manager of one of the Schlumberger Cased Hole Wireline Units. I asked him if there had been any changes in their field operations since Peter Fitzgerald (Schlumberger) had been granted a patent on creep in January, 2009. He acted as if he did not know what I was talking about. He then admited that there had been no changes in their field operations to detect or adjust for creep.

The perforating companies are the ones who should be interested in solving this problem. I am shocked at the industry's lack of interest or concern about this problem. Good wells are being abandoned because of this, acerage is being condemned because wells that should be good tested "dry".

NONE of the perforating companies have been willing to talk with me about solving this problem. If any of you have suggestions about how I can get them to see the seriousness of this problem.

Something to report: A well in Oklahoma was attempting a completion in the Morrow Formation at a depth of 16,500'. Creep was determined to be 17' in that well using that equipment. The Morrow was only 15' thick. After adjusting for 17' of creep, the well was perforated and tested at 10.4 MMCF/D. If creep had not been determined and adjusted for, the operator woud have gotten a dry test and abandoned the zone. This creep problem is really critical when perforating thin zones.

Another report: a well in Nigeria had about 13' of creep at a depth of about 12,900'. It was stated that although the pay was thick and 13' of creep would not normally be critical, this well was to be gravel packed for sand control. Had creep not been determined and compensated for, there would have been 13' of shale perforated and gravel packed. Almost all sand control schools warn us about perforating shale in gravel packed wells. The shale will eventually begin to break up, migrate into the pack and kill the well.

Rework,

Very interesting thread! I am not too much involved with drilling/logging/completion operation but do see the impact this can have on the business. If this is truly as neglected as you state it is then this can be a huge thing. Am very interested in your endeavors on how you are getting this across to the teams involved and if you have had further experiences since your post 5 months ago.

thanks,

Frans

I have been absolutely amazed at the lack of interest in this critical part of completions. I visited with a large independent oil company in Tulsa recently, and they had a classic example of this problem. They completed in a thin zone at around 14,000' and then fraced the well. They had a hard screenout on the frac job, and production was much less than expected. I offered to reperforate the well AT NO COST TO THEM and provide them with proof that creep was their problem. They did not take my offer - AMAZING!

About a week later, I talked with the owner of a company that adds redioactive tracers to frac fluids. He stated that rarely are the perforations where they schould have been. I plan to negotiate a deal with him to obtain examples of the proof of creep he has experienced. Sometimes, I get so frustrated that people do not seem to care about this problem.