There is much said about completion design and how it equates to EURs. Everyone's model is a little different, and given the recent changes, it is difficult to know what variable will influence this number the most. Since most companies tend to increase the number of stages, volumes of water and amount of proppant in concert, it is hard to know what is the most effective. Continental Resources, Inc. (CLR) has made a big move in all three and has seen much better initial production results, which I covered in this article. Whiting Petroleum Corporation (WLL) has increased the number of stages used, but has kept its water volumes and proppant usage at lower levels, which I had addressed in this article. EOG Resources, Inc. (EOG) continues to use short laterals and is also starting a waterflood program in Parshall Field.
One company gets very little attention in the Williston Basin. Given its size and other projects the Bakken is not generally associated with Exxon Mobil Corporation (XOM). When Exxon purchased XTO in late 2009, it was buying a predominantly natural gas producer. This purchase also provided for some very good acreage in Dunn and other counties. Working as XTO in the area, it also became the operator of acreage shared with Kodiak Oil & Gas Corp (KOG). Kodiak's well design is much like Exxon's and may be where it learned much of its know-how, but that is just an assumption on my part.
Exxon's acreage in Heart Butte Field has recently seen some increased activity. It is located in north Dunn County, just south of Mandaree, North Dakota. Given the recent activity and good geology, I used this as an area to focus on Exxon's results. In the table below, I have listed 2011 well results.
2011 XTO Heart Butte Field Results
| Name | Date | Choke | Stages | Water | Proppant | 60-Day IP | 120-Day IP |
| FBIR 21X-10 | 12/11 | 20/64 | 24 | 62653 | 3227266 | 314 | 345 |
| FBIR Darcie 34X-14 | 12/11 | 24/64 | 24 | 56949 | 3286788 | 239 | 157 |
| FBIR Stephen 31X-19 | 8/11 | 24/64 | 24 | 58385 | 2851560 | 470 | 419 |
| FBIR Bird 31X-19 | 8/11 | 24/64 | 24 | 61513 | 2659611 | 588 | 508 |
| FBIR Smith 11X-10 | 10/11 | 18/64 | 30 | 65920 | 3244148 | 661 | 594 |
| FBIR Baker 34X-25 | 7/11 | 32/64 | 18 | 51115 | 2521911 | 216 | 248 |
| FBIR Walker 34X-25 | 7/11 | 24/64 | 18 | 53724 | 2545880 | 295 | 339 |
In the table above, there are some pretty good results. There were a few wells that Exxon had some difficulties with, which limited 30-day IP rates but were then brought back on line and have been producing quite well. The wells that have higher 120-day IP rates than 60-day are those wells and should be focused on from a longer time frame given those issues. Its best well not only had the largest number of stages at 30, but also the highest water volumes and the tightest choke. In the table below are its 2012 completions in the same field.
2012 XTO Heart Butte Field Results
| Name | Date | Choke | Stages | Water | Proppant | 60-Day IP | 120-Day IP |
| FBIR Yellowwolf 21X-10 | 1/12 | 20/64 | 24 | 58529 | 3271243 | 391 | 389 |
| FBIR Walterpackswolf 31X-12 | 2/12 | 32/64 | 24 | 62414 | 3033093 | 405 | |
| FBIR Huntsmedicine 24X-8 | 4/12 | 20/64 | 24 | 64388 | 3306501 | 605 | |
| FBIR Guyblackhawk 24X-27 | 2/12 | 24/64 | 24 | 62007 | 3128171 | 739 |
Exxon is staying consistent with respect to its completion design, and has had very good success. Some of the numbers are skewed, given problems with production for the first month of the well, but later this is rectified in all cases in this field. At this point, Exxon continues to favor fewer number of stages and larger water volumes, which I think could be as important, if not more, as the number of stages itself.
Disclosure: I have no positions in any stocks mentioned, and no plans to initiate any positions within the next 72 hours.
