I understand that CHK and others have "production curtailment" policies in place due to the current price of NG. Would that not causes a steeper decline curve for the formation? For example, a well is completed at an IP of 20 MMCFD with a 20/64 choke. It is allowed to run at this rate for one month to clean out the flowback. Then, under "production curtailment", it is choked down to 5 MMCFD. If you average the monthly production for all the wells in the HS, this would skew the average toward a very sharp decline which then wouldn't be a true reflection of the potential of the well. Or, am I wrong and is the decline curve predicted based on other data?

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GL, the well operators' develop type curves based on stabilized flow conditions and should make the necessary adjustments. Outsiders, on the other hand, would not be aware of these circumstances and could end up with a distorted picture of the typical decline curve.
For outsiders who only rely on production reports on SONRIS, we have NO way of knowing about curtailment for economic or other reasons. Sometimes you get it from a con call or press release. For example, EOG's two Desoto wells, Martin 2 and Bledsole 27, were IP'd at 17.4 and 17.5 mmcfd, but EOG said in its call that each was being produced at 8 mmcfd because of pipeline capacity constraints. Also, HK said it had taken Sample 4 out of its IP average because of mechanical problems in completion (even though it did 5+mmcfd) and it intended to shut the well for recompletion (which HK did).

CHK ( following its usual non-disclosure, non-reporting posture) tells you nothing on SONRIS or otherwise. It purports to have three 20+ IP wells, but only one has been identified and that was by STR, not CHK. CHK reports positive things when it is hyping CHK stock; negatives or required filings with LDNR are ignored.
Choke only has to be reported along with the required well tests. We regurlaly will change chokes on our wells, and no report to the state is required unless we try to get a different allowable.
The main thing the State wants to know is, how much oil, gas, and/or condensate the well makes so they can be sure to get their severance taxes and give royalty owners a way to make sure thay are being properly paid.
Very good point Jim. The companies have 60 days to report to the State. But they can go to their investors and tell them the day after the test. More than likely, CHK has tested the wells within the last 60 days and told Wall Street. The data reporting is in progress and will make it into the State data stream. Probably. Maybe almost certain. Ok, KB, some companies push that 60 day term to its limits and then some.
Is there a requirement, with teeth or without, which requires reporting of changes in choke and if so is this reflected on SONRIS?
Yes, choking the well back will flatten out the decline curve and slow its approach to semi-steady state. Watch the flowing pressures reported with the rates. That's an important number. If the well makes 20 MMCF at 3000 psi, then 10 MMCF/day at 4000 psi, then that well is choked back. It could continue to make 10 MMCF/day for a while, but watch the flowing pressure. It will start to decline and at some point, the rate will have to start declining due to the hydraulics of the reservoir/well system.
Nobody reports psi flow pressures after the test. All you get is the monthly production. And PVA reported that choking back early horizontals because of pipeline constraints seemed to negatively impact the wells after opening the chokes back to "desired" size.
Yeah. But many of the companies are choking the wells back considerably due to prices. So if one has access to FTP's, then they can get a better indication of how much constraint is being put on the well. Just a handy dandy indicator.
OK, what physically are we talking about in this context when we say "choke"?

Is it a chunk of metal with a hole in it that you remove and replace with similar chunk of metal with a different sized hole? Or is it some sort of valve analogous to adjusting the faucet on the kitchen sink?
Thanks. I wonder why they use that vs. a mechanically adjustable valve. Or do they use both?

Do they have remotely operated controls to dial the wells up/down/on/off in real time? I had a family member who worked for a gas company and he talked about having to have the wells adjusted or turned on beforehand when there was going to be a cold snap.
Mac, typically the chokes have to be adjusted manually and do not have remote access. The exception is in the North Sea some wells on unmanned platforms have remotely adjustable chokes.

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