Evidence Of Communication Between Wells -- November 17, 2015

Updates

April 26, 2016: in the original post, it was noted that #26158 was taken off-line (status: inactive). As of November, 2015, this wells was back on line:

• 26158, 3,771, Statoil, Johnston 7-6 3TFH, Banks, t11/14; cum 67K 2/16;

Pool	Date	Days	BBLS Oil	Runs	BBLS Water	MCF Prod	MCF Sold	Vent/Flare
BAKKEN	2-2016	22	6895	7397	7691	12292	11236	591
BAKKEN	1-2016	25	13396	13316	12341	22228	20262	978
BAKKEN	12-2015	28	16274	16317	14975	27740	26382	177
BAKKEN	11-2015	21	12614	12039	18486	25698	23888	965
BAKKEN	10-2015	0	0	0	0	0	0	0
BAKKEN	9-2015	0	0	0	0	0	0	0
BAKKEN	8-2015	0	0	0	0	0	0	0
BAKKEN	7-2015	0	0	120	0	0	0	0
BAKKEN	6-2015	8	3838	3826	1834	5467	5028	439
BAKKEN	5-2015	27	4147	4221	2267	18398	14921	3477

 

Original Post

 

This is a long note. There will be typographical and factual errors. I may be seeing things that do not exist. If this is important to you, go to the source.

While looking up this well for other reasons I happened across this little gem, which is another pixel in the Bakken mosaic, helping me to better understand the Bakken.

29564, SI/NC, Statoil, Skarston 1-12 XE 1H, Banks, no production data,

I think this is a big, big deal, but then I am inappropriately exuberant about the Bakken. I get excited about a lot of things that turn out not to be so exciting and I have been accused of "childlike glee" (yes, that accusation followed one of my book reviews over at Amazon.com).

So with childlike glee and with inappropriate exuberance I post the following -- a small excerpt -- from the file report on this well:

As a measured depth of 20,411', April 4, 2015, the decision was made to stop and circulate out gas while transferring mud and increasing the mud weight. The decision was then made to continue to circulate off bottom while preparation could be made to switch the drilling fluid to oil-based mud. The oil-based mud was then increased to 12 ppg. It was found that even with 12 ppg oil-based mud, the shut in casing pressure (SICP) continued to increase while the well was shut in. It was then decided that the mud weight should be increased further to near 14.2 ppg. This process took several days to complete.

It was later discovered that the unidentified mineral was in fact, ceramic proppant. This is sometimes used as frac sand, or in conduction with quartz sand. It was also later confirmed, that there was in fact communication with an adjacent well that had been recently completed. 

It was believed that this communication between wells was causing the increased pressure and fluid gains.

This adjacent well was the Statoil Johnston 7-6-3TFH (#26158).

The mud weight was increased to 14.2 ppg....after drilling resumed, the pressure increased, and fluid gains were seen. The decision was then made to shut the well in and circulate bottoms up. This yielded a trip gas of 4,602 units, and a large flare ....
...drilling resumed .. while drilling ahead within the lateral, the ROP was near 35 ft/hr.

The slow ROP was due largely to the high mud weight. This caused the pump pressure to be near the maximum pump pressure rating of 5,000 psi at half pump strokes of the previous salt water driling fluid. Even with the high mud weight, slow ROP, and going through the gas buster, the background gas was near 750 units, and a 3 - 10 foot flare produced.

While nearing the end of the drilling, the report continues:

Bottoms up was circulated through the choke, after getting back to bottom. This resulted in a 10'flare and a trip gas of 6,282 units. ... [several challenges ensued]...the lateral was called TD at 20,823 feet (approx 1225 feet early) on April 14, 2015.

Separation and formations:

Horizontal separation between the laterals of the Skarston well and the Johnston well: about 600 feet. 

Vertical separation between the two laterals, approximately, 130 feet, it appears.

• The Skarston well, TVD = 10,903 feet
  The Johnston well, TVD = 11,035 feet

The target formations:

• Skartson: middle Bakken
• Johnston: Three Forks

The Johnston well:

• 26158, IA/3,771, Statoil, Johnston 7-6-3TFH, Banks, 35 stages, 4.5 million lbs sand and ceramic, t11/14; cum 18K 9/15; there is no information in the file report why this well is now inactive 

Pool	Date	Days	BBLS Oil	Runs	BBLS Water	MCF Prod	MCF Sold	Vent/Flare
BAKKEN	9-2015	0	0	0	0	0	0	0
BAKKEN	8-2015	0	0	0	0	0	0	0
BAKKEN	7-2015	0	0	120	0	0	0	0
BAKKEN	6-2015	8	3838	3826	1834	5467	5028	439
BAKKEN	5-2015	27	4147	4221	2267	18398	14921	3477
BAKKEN	4-2015	30	0	0	0	0	0	0
BAKKEN	3-2015	31	0	0	0	0	0	0
BAKKEN	2-2015	28	0	0	0	0	0	0
BAKKEN	1-2015	31	0	0	0	0	0	0
BAKKEN	12-2014	31	0	0	0	0	0	0
BAKKEN	11-2014	30	10319	10137	16985	0	0	0