Sunday, August 17, 2014

Random Note On New "400-Series" EOG Wells In The Parshall -- August 17, 2014


August 23, 2014: another "400-series" well:
  • 29190, SI/NC --> TATD --> 622, EOG, Parshall 406-34H, Parshall. The well file is still accessible -- proposed "objective horizon": Bakken; spacing unit: 640 acres, TVD, 9,320 feet; TD, 14,968 feet. EOG estimates the top of the middle Bakken (which is listed as the target) at 9,303 feet; the lower Bakken shale at 9,341 feet; and the Three Forks at 9,374 feet; spud October 14, 2014; FTD, October 21, 2014; 5,263 feet in the middle Bakken target; in zone, 100%); 21 stages; 5.1 million lbs; t11/16; cum 47K 5/17; 
Original Note

[Note, unrelated to this post: St Demetrius oil field has been updated.]

At the bottom of the blog, there is a large section of "tags." One of the tags is "nomenclature." I haven't caught all the posts that have to do with "nomenclature" or the naming of wells in the Bakken, but I have several, at least enough to get started for those interested.

Some operators name their wells so that we know which formations are being targeted. When the Bakken boom began, all "H" wells were horizontal wells (that's what the "H" stood for and most of the wells were targeting the middle Bakken); if you saw an "H" in a name for a permit after 2007 in North Dakota, you could be pretty comfortable knowing it was in the "Bakken Pool."

When operators started targeting the Three Forks, many of them preceded the "H" with "TF" --> TFH or a Three Forks Horizontal. (Subsequently, Whiting uses "PH" for Pronghorn formation in the southwest part of the state, similar to Sanish in Mountrail County.)

Generally speaking, any well permitted/drilled before the end of 2012 with a TFH designation and/or any well drilled prior to the end of 2012 in which the geology report/file report says Three Forks, one can assume the target was the "upper" Three Forks.

Some time after 2011 or 2012 (I've long forgotten when this all evolved), we started hearing CLR and Whiting discuss lower benches of the Three Forks. The shorthand is now TF1 for the upper Three Forks; TF2 for the second bench, TF3, for the third bench, and TF4, for the fourth bench (I think I'm correct on that -- but I could be wrong).

Be that as it may, some operators stay with the single letter "H" for horizontal and do not use letters to suggest which formation will be targeted.

For example, this Hess well will target the Lodgepole:
  • 26738, TA-->A-->103, Hess, Ti-Wao-157-95-14H-1, Tioga, this is a Lodgepole well, t7/14; cum 27K 5/17;  
Another example: EOG.

EOG wells are fairly standard in the Bakken:
township/location/family name -- one, two, or three digit number -- dash -- two or four digit number -- H
So, a typical EOG well name looks like this:
West Clark 1-2413H
Pretty simple.

The "1" is simply a chronological number which I will return to later.

The "2413" number is the area under which the horizontal will run; in this case the well is sited in section 24 and will end in section 13.

Another well:
Parshall 13-26H
The "13" is the chronological number; the well is a short lateral, running under section 26.

Now back to that chronological number, "1" in the first example, and "13" in the second example. I discussed this a long, long time ago, and I could be wrong, but generally, it appears, for EOG, a chronological number in that location (coming right after the township/location/name) suggests which formation the original permit application provided:
  • 1 - 99: middle Bakken (up to 99 middle Bakken wells in one spacing unit)
  • 101 - 199: upper Three Forks (up to 99 upper Three Forks wells in one spacing unit)
This generally holds true for EOG, but exceptions can be found, where a "1-99" well ended up being a Three Forks well, and a "101-199" well ends up being a middle Bakken well. One generally needs to go back to the original permit and things generally line up correctly; it appears that on occasion the target changes between the time of the permit and the completed well.

The reason for all this is that in the last week or so, EOG has introduced a new three-digit number, what I call the "400-series":
  • 29127, TATD--> 1,584, EOG, Parshall 401-3534H, Parshall, sections 35/34 - T152N-R90W, 1280-acre spacing, TVD of 9,300; TD of 15,717; 340 FSL; 1410 FEL; "Bakken," azimuth, 319.6; a "grass-roots horizontal"; middle Bakken; spud date, December 3, 2014; FTD date, December 12 2014; middle Bakken target - 100%; t11/16; cum 49K 5/17;
  • 29126, TATD --> 955, EOG, Parshall 402-3534H, Parshall, sections 35/34 - T152N-R90W, 1280-acre spacing, TVD of 9,300; TD of 16,119; 340 FSL; 1460 FEL; "Bakken," azimuth, 320.5; t11/16; cum 72K 5/17;
  • 29105, TATD--> 953, EOG, Parshall 405-3534H, Parshall, sections 35/34 - T152N-R90W, 1280-acre spacing, TVD of 9,335; TD of 15,189; 650 FSL; 2050 FWL; "Bakken," azimuth, 320.1; t11/16; cum 56K 5/17;
  • 29104, TATD--> 1,221, EOG, Parshall 404-3534H, Parshall, sections 35/34 - T152N-R90W, 1280-acre spacing, TVD of 9,335; TD of 15,773; 650 FSL; 2000 FWL; "Bakken," azimuth, 320.0; 22 stages; 5.8 million lbs;  t11/16; cum 50K 5/17;
  • 29103, TATD--> 780, EOG, Parshall 403-3534H, Parshall, sections 35/34 - T152N-R90W, 1280-acre spacing, TVD of 9,335; TD of 16,569; 650 FSL; 1950 FWL; "Bakken," azimuth, 320.0;  t11/16; cum 51K 5/17;
I don't believe #29126 and #29127 are yet plotted on the NDIC GIS map (August 17, 2014). 

So a couple of things.

First, the new three-digit number designating the formation, a new series, the "400-series." Looking at two other EOG wells in the immediate region provides no clue: the two nearby short-lateral wells targeting the middle Bakken have similar TVDs and TDs. The thickness of the various formations in the Bakken Pool (MB, TF1, TF2, TF3, and TF4) are very thin so even 50 feet makes a difference, but I certainly can't sort this out based on this information.

All five of these wells have almost identical azimuths of 320 degrees, making them all parallel with each other. The hypotenuse of a one-mile square section is 7,467 feet; the longest horizontal is about 6,800 feet (TD - TVD), which suggests that these horizontals will all parallel each other, start in section 35, and end in section 35, but they will be spaced at 1280-acre spacing (sections 35 and 34).

This is way beyond my comfort zone; and, I may be misreading something, but that's how I see it right now: a new "400-series"; depths that aren't helpful to figure out which formation might be targeted; and all appear to be short laterals in "long-lateral" spacing (if that makes sense.).

So, I will throw that out there, and see if anyone has any thoughts. Perhaps it's obvious to everyone else, and it's just me missing the obvious.

There is another "408" well out there:
  • 27850, dry - a monitoring well, EOG, Parshall 408-15M, Duperow; it is located in 15-152-90, 3.5 miles almost due north (NNW) of the five locations in section 35-152-90, but the application says this "408" well is simply a monitoring well that will monitor two middle Bakken wells located in section 15 (#27291, #27292) and will not produce any oil.
Certainly the "400-series" wells in section 35 are going to be producing wells. It's hard to believe that "400-series" wells are Duperow wells. First, the forms for those wells say "Bakken"; second, it would seem unusual to place five Duperow wells all at one time in one section? And I think the Duperow, being deeper than the Three Forks, might mean a deeper TVD, even though that's much more difficult to sort out.

There are good Duperow wells, for example this one, about three-quarters of a million bbls since 2008:
  • 7141, 521, Wesco, Hamre 1-14, Cherry Creek, Duperow;  s8/79; t2/80; cum 824K 5/17;
So, there you have it. That's all I know. Something tells me it's going to be a simple explanation and I wrote this long post for nothing.

Lodgepole? Lodgepole is part of the Bakken pool. Oasis has drilled Lodgepole wells using standard Oasis nomenclature.

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