tag:blogger.com,1999:blog-5552647839482265343.post8705688766377682292..comments2019-08-04T20:46:36.888-04:00Comments on peak oil climate and sustainability: Update to North Dakota Bakken / Three Forks ScenariosDennis Coynehttp://www.blogger.com/profile/17688179289708969899noreply@blogger.comBlogger5125tag:blogger.com,1999:blog-5552647839482265343.post-41313050744032741192013-10-03T18:40:19.425-04:002013-10-03T18:40:19.425-04:00Sorry for the delay in responding. (I converted yo...Sorry for the delay in responding. (I converted your images in the comments to display over at http://ContextEarth.com, btw)<br /><br />I did use an OU profile for the latest fit and the mean is 280,000 barrels cumulative. I also did the painstaking job of pulling each of the monthly records so that I would get a true cumulative count instead of the "active" count that the NoDak crew puts on their site. <br /><br />I think the strong flattening of the OU curves is vital to getting a good fit because it simulates the wells that have been shut in and gone inactive after some time. OTOH, if we only consider the active wells, then the hyperbolic curve seems to work better. The reason for this is the weeding out of the inactive curves does the cumulative flattening.<br /><br />I will look into first 24 months of data some more. <br /><br />WHThttps://www.blogger.com/profile/18297101284358849575noreply@blogger.comtag:blogger.com,1999:blog-5552647839482265343.post-43787701927187285512013-09-27T18:11:36.464-04:002013-09-27T18:11:36.464-04:00WHT,
I agree if you mean the EUR(30) for the aver...WHT,<br /><br />I agree if you mean the EUR(30) for the average well in the ND Bakken/ Three Forks. I have not tried the server yet, What did you use for your well profile? Is it a hyperbolic or OU diffusion? I commented on your blog recently, basically I was commenting on the OU diffusion model an the difficulty with fitting to short term data (24 to 36 months), it seems a hyperbolic fit to the 24 months of data we have and then fitting an OU diffusion model to the hyperbolic works best, then a hybrid hyperbolic/ OU diffusion model can be used where a hyperbolic is used for the first 24-30 months with an OU diffusion model thereafter. I forgot to include the oil produced in my TRR estimate, when this is added the mean USGS ND Bakken/Three Forks TRR becomes about 8.4 BBO.<br /><br />DCDC78https://www.blogger.com/profile/17688179289708969899noreply@blogger.comtag:blogger.com,1999:blog-5552647839482265343.post-83480969602418452082013-09-27T16:09:06.182-04:002013-09-27T16:09:06.182-04:00I am thinking the average won't go over 300K
G...I am thinking the average won't go over 300K<br />Good work<br /><br />Have you tried the server yet?<br />http://entroplet.com/context_bakken/navigate<br />WHThttps://www.blogger.com/profile/18297101284358849575noreply@blogger.comtag:blogger.com,1999:blog-5552647839482265343.post-82774709455058908402013-09-25T09:55:32.760-04:002013-09-25T09:55:32.760-04:00Hi Clifman,
You are almost correct, but the Mediu...Hi Clifman,<br /><br />You are almost correct, but the Medium scenario matches pretty closely with the mean USGS estimate and is not an optimistic estimate. Keep in mind that the “average well” does not remain the same over time. The math (except maybe the hyperbolic function) is mostly just arithmetic (I do not have the math chops of WHT). Your 16 BBO estimate is pretty much spot on, but it would need to assume that EUR never decreases and the entire Bakken/Three Forks play has uniform well productivity. In other words, either there are no sweet spots or technology advances so rapidly that it counteracts the decreasing EUR so that the average EUR of new wells remains constant over time. I do not believe that either of these optimistic scenarios will be the case, the EUR of new wells will eventually decrease as the sweet spots get drilled up.<br /><br />How does the TRR get to be 8 BBO rather than 16 BBO for the Medium scenario? Take a close look at figure 3, especially the blue curve. If I had made my model a little less “realistic” and the blue curve were a straight line between Jan 2014(100 %) and Dec 2033 (0 %) then we would be at 50 % of the Jan 2013 EUR in 2023 and our “average well” over the entire 2014 to 2033 period would have an EUR of 170 kb.<br /><br />When we multiply 170 kb by 48000 wells we get about 8 BBO, so my medium scenario matches up pretty closely with the USGS mean estimate and is not as optimistic as you imagine.<br /><br />Note that the high scenario does not work as well when we do the same kind of simple estimate and the TRR approaches 10 BBO rather than the 11 BBO shown in figure 1. This is because I take the TRR out to Dec 2073 so these “high” scenario wells have been producing at least 40 years (2033 to 2073) rather than 30 years.<br /><br />For the high scenario the EUR(40)(40 year EUR) is 475 kb and our estimate becomes 11.4 BBO, using the straight line assumption for the decrease in EUR.<br /><br />Hope this helps.<br /><br />Dennis Coyne<br />DC78https://www.blogger.com/profile/17688179289708969899noreply@blogger.comtag:blogger.com,1999:blog-5552647839482265343.post-70719396796322955492013-09-24T10:27:47.237-04:002013-09-24T10:27:47.237-04:00Dennis - While (I think) I totally grok the concep...Dennis - While (I think) I totally grok the concept of diminishing returns that you, WebHT, AB & others point out about the Bakken, my understanding of your analytic math is rudimentary. So I did a simple check. Tell me if this makes sense: I multiply the mid-range total output of a well from figure 2 (rounded to 350,000) by the rounded total wells drilled figure of 45,000, and I arrive at 15.75 BBO. So that tells me that if anything, your figures are optimistic relative to the USGS high estimate of 11 BBO. Does this make sense? Thanks for your great work on this!clifmanhttps://www.blogger.com/profile/02957733800798868055noreply@blogger.com