Re-posting. This is a huge well. This page will not be updated. The CLR Wahpeton wells are tracked elsewhere.
Coming off confidential list today. Again, except for the updated production numbers reported today, this is a re-posting from an earlier note:
This is a huge "testament" to the skill of all involved. It sounds they had more than their share of difficulties on this well, and it still came in as a great well!The well:
The "original" Wahpeton wells came in less remarkable than I expected, but, all of a sudden, we have a great Wahpeton well.
- 35913, F/A, CLR, Wahpeton 15-16HSL (2560 acres), Banks, fracked 12/19/2019 - 12/28/2019; 8.5 million gallons (small-to-moderate); 87.8% water by mass; friction reducer not remarkable; target: middle Bakken;
Pool Date Days BBLS Oil Runs BBLS Water MCF Prod MCF Sold Vent/Flare BAKKEN 5-2020 31 35697 35797 23615 63681 63677 0 BAKKEN 4-2020 30 31263 31228 24175 47345 47341 0 BAKKEN 3-2020 31 50720 50843 38513 75713 75713 0 BAKKEN 2-2020 7 18557 18162 13712 23382 22896 486 BAKKEN 1-2020 6 357 357 5508 540 0 540
Of note from the file report:
Salt water disposal wells in this vicinity have caused salt water gain issues in this vicinity when drilling through the disposal formation (Dakota supergroup). A single geologist was tasked with being on site during drilling of the Dakota to verify the top and the base of the Dakota sandstone members, after which the rig ran and cemented 9.625” casing. This well was the second in a line of four and represented an improvement from the problems of the first well. We still suffered losses in the uppermost of the Inyan Kara sands, but upon switching from heavier to lighter brine mud while holding back pressure on the choke, we were able to better control both losses in the uppermost sand and water intrusion from the water disposal layers. The biggest engineering problem came from casing locking in place at the top of the last sand. Cement was pumped into place with the hope that it would return to surface and fill the intervening hole and keep water intrusion from occurring. Both hopes were realized.Also of note, from the file report:
Bakken shale collapse issues are of lesser, but still manifest, concern in this area, and angles of intercept and shale exposure footage remain important data. Continental engineers have determined that entering the shales should be done at angles no more than 65-68° of inclination. On this well, the Upper Bakken was intercepted at 67.05° and exited at 72.47°, with a total of 48’ of shale exposure. No shale collapse issues occurred.From the file report:
- big rig began drilling on the evening of June 7, 2019
- vertical operations required an amazing six BHAs; generally it is only one, maybe two;
- sounds like they had challenges landing the curve
- drilled out of the shoe on the afternoon of July 25, 2019
- lateral required only one BHA;
A single BHA sufficed to get us through the horizontal section to TD. Unfortunately, due to poor markers and use of the Jamestown 14-17 HSL1 for structural control, which ended up showing a 20’ difference to TD on this well, we ended up in the fog gamma (which locally has more character than generally expected in the basin), and struck the Lower Bakken Shale 256’ from TD. Continental management, rather than sidetracking, decided to call the well complete at that point.Finally:
completed on July 27, 2019;
The Jamestown Federal 14-17HSL1, previously drilled on this pad, was used for lateral structure control.Unfortunately, TF1 and Middle Bakken wells are sometimes poorly reconciled, even when close to each other, and the TD points of both wells, well controlled by gamma data, were 20’ different in TVD, which led to a Lower Bakken strike at the end of the well, as mentioned above.This phenomenon was judged to be a break between Three Forks and Middle Bakken structure, as the same differential downward would occur on the Wahpeton 16-16H1, which had a structure very similar to the Jamestown 14-17HSL1.How to explain this is unknown currently.
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