A Stratigraphic Study Of The Tyler Formation -- Southwestern North Dakota

Recently I took a look at Amsden / Tyler formation in the Dickinson area. I downloaded a PDF but was unable to get the link to make it easy to share on the blog.

I tried something different tonight. I have no idea how it works, why it works, and whether it will work for you, but here is the link for a 2017 UND thesis on the Tyler formation in the Dickinson oil field, southwestern North Dakota.  

If it works, great. If not, google sequence stratigraphy of the tyler formation and then download the pdf that will pop up. 

Enerplus' "Precipitous Ridge" Pad

From earlier today:

Seven new permits, #37868 - #37874, inclusive (permits renewed September 27, 2024):

• Operator: Enerplus
• Field: Antelope (McKenzie)
• Comments:
• Enerplus has permits for a 7-well "precipitous ridge" pad (Flatiron, Shoal, Fjord, Hogback, Arroyo, Barchan, and Cirque) -- see below) in NWNW 28-152-94, 330' NFL and 1068' to 1278' FWL; 

The geologic structure terms:

• flatiron: a steeply sloping triangular landform;
• shoal: a natural submerged ridge, bank, or bar; also known as sandbars, sandbanks, gravelbars;
• fjord:
• hogback: a long, narrow ridge or a series of hills with a narrow crest and steep slopes of nearly equal inclination on both flanks
• arroyo:
• barchan: crescent-shaped sand dune
• cirque: amphitheatre-shaped basin with precipitous walls

Speaking of shoals:

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October! Welcome!

 

Random Excerpt From An Oasis Mallard Well In Alger Oil Field -- April 3, 2015

A portion of the geologist's report from:

• 26382, 331, Oasis, Mallard 5692 21-20 9T2, Alger, TF2, 36 stages; 4.3 million lbs, t8/14; cum 12K 1/15;

This, of course, pertains to this particular well, this particular area, but it provides newbies an idea of the various payzones in the Bakken.

The Mission Canyon Formation (Mississippian - Madison Group) was observed at 8,494' TVD (- 6,190). Representative samples consist of a light brown and gray microcrystalline limestone with trace-light brown oil stain. Some samples contained moderate traces of algal material. Increases in background gasses from 50 to 100 units and several shows above 120 units supported possible trace intercrystalline porosity, not visible in sample.

The Middle Bakken Member of the Bakken Formation (Late Devonian-Early Mississippian) was drilled at 9,845' TVD (-7,541'). Representative samples consist of a medium gray to light brown, calcareous silty sandstone with moderate intergranular porosity and a trace light brown oil stain. Samples in this interval exhibited fast, diffuse, off white cut fluorescence. Moderate hydrocarbon show and heavy gases (C1-C4) were observed throughout this interval, peaking at a show of 121 units.

The Lower Bakken Shale (LBS) of the Bakken Formation (Late Devonian – Early Mississippian) is a dark brown and black carboniferous shale deposited in an open marine environment. The Lower Bakken Shale is well known for its hydrocarbon content and is commonly thought to be a “charge zone” for the Three Forks. During drilling of the LBS, observed at 9,900’ TVD (-7,596’), gas shows peaking at 223 units and abundant black oil stain was observed in all 40’of this interval.

The Three Forks Formation (Late Devonian) has been divided into three potential productivity zones or “benches” of interest by Oasis. Each bench is divided by a “claystone” member that is lower in porosity and very silty, making them of less interest as potential pay zones. The Three Forks was deposited as a result of a second-order stratigraphic sequence regression within the Kaskaskia major sequence in a supratidal marine environment, resulting in evaporates, bio-turbated and wave-sorted clastics, and paleosols.

The First Bench of the Three Forks Formation is located just below the Pronghorn Member of the Bakken Formation. The first bench is well known for interbedded shale and dolomite, characteristically having good porosity and common hydrocarbon show in sample cuttings. Samples while drilling were observed as an off-white and rare pink dolomitic mudstone, with moderate to rare intergranular porosity, interbedded with mint green shale containing abundant disseminated pyrite and very little visible porosity. The First Bench was drilled at 9,945’ TVD (-7,641’), though no gas shows were observed due to a broken trap motor. Hydrocarbon cuts exhibited moderate white streaming cut fluorescence.

The Second Bench of the Three Forks was the primary target for the lateral portion of the Mallard 5692 21-20 #9T2 and was entered at 9,990’ TVD (-7,686’). Three distinct lithologies were observed during drilling of the lateral, with various interbedding of the first two throughout the 30’ thick section, represented in a type log for the Second Bench of the Three Forks. The first lithology was observed at the C and E markers and consisted of a very clean, sucrosic white and pinkish orange dolomite with moderate intergranular porosity. This lithology was observed several times throughout the lateral and produced moderately quick and predictable drilling rates.

The second lithology observed in the lateral corresponded to the B and D markers, with high gamma characteristics. It consisted of a dolomitic siltstone, light to medium gray in color with very silty tendencies. Very little porosity was visibly observed in this lithology with slow and weak hydrocarbon cut shows. Drilling in the B and D sections of the target zone produced fair drilling rates and little bouncing of azimuth or inclination.

The third lithology was observed in the lower portion of the target zone and in the last third of the lateral. A red-orange silty mudstone with low porosity was described as microcrystalline with a sucrosic texture. This lithology became the most commonly observed in the lateral as drilling to the east progressed.

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The Clues Are Hard To See

I track this story elsewhere, but an update --

April 3, 2015: this provides some insight into the incredible lack of psychological insight investigators have. WTOP is reporting:

The co-pilot of the doomed Germanwings flight repeatedly sped up the plane as he used the automatic pilot to descend the A320 into the Alps, the French air accident investigation agency said Friday.

The chilling new detail from the BEA agency is based on an initial reading of the plane’s “black box” data recorder, found blackened and buried at the crash site Thursday.

It strengthens investigators’ initial suspicions that co-pilot Andreas Lubitz intentionally destroyed the plane — though prosecutors are still trying to figure out why. All 150 people aboard Flight 9525 from Barcelona to Duesseldorf were killed in the March 24 crash. 

Let's review the clues:

• history of psychiatric depression requiring 18 months of intensive therapy
• suicidal ideation
• 11 months as a flight attendant when flight training interrupted due to severe depression
• likelihood of losing his job due to eye problems (likely to have been psychosomatic)
• "fear of flying"
• sexual identity issues
• broke up with his girlfriend almost immediately before the flight
• doctor's recommendation that he not fly (had this come to attention of his employer, it should have ended his flying career)
• he said that all he ever wanted to do in life was fly for Lufthansa
• not yet flying for Lufthansa per se, but a subsidiary airline
• a loser

Garnet Oil Field, Williston Basin, North Dakota

The Garnet oil field is on the northern edge of the Bakken play in North Dakota, an area where one would expect to find Three Forks wells. This is a very small rectangular field, only 8 sections (2 x 4). Six of the eight sections have a long lateral (3 wells); sections 1/12-161-99 do not yet have a well. It is located in the middle of Divide County.

In a long post like this, there will be typographical and factual errors. If this information is important to you, go to the source, generally the NDIC webpage. 

• 25938, 377, SM Energy, Windfaldet 2-4H, Three Forks; 11-foot thick target zone which included an upper 6' of dolomite sandstone, 26 stages; 2.4 million lbs sand, middle Bakken 60-feet thick here; max gas units, 600; 1280-acre; t1/14; cum 44K 8/14;
• 24192, 318, Baytex, Pulvermacher 3-10-161-99H 1XN, Three Forks, gas units max, 1,700; target, a 5-foot thick target zone directly above the Three Forks Shale, identified by a gamma marker known as the Three Forks 10 Mrk; Dolostone sandstone; 36 stages; 1.6 million lbs sand; 1280-acre; t5/13;cum 57K 8/14;
• 21849, 28 (scout ticket), Baytex, Thompson 2-11-161-99H 1BP; 30 stages; 2.1 million lbs sand; 1280-acre; t3/12; cum 69K 8/14;

Formation tops, for #24192:

Blue: sample and gamma
Yellow: prognosis
First blue column: TVD
Last yellow column: Top v. Prog

Monster "Snake" Wells In Antelope Oil Field -- October 10, 2014

Locator: 10010SNAKE.

 

Updates

May 6, 2024: these monster wells updated.

May 22, 2020: these monster wells updated.

January 11, 2019:

• 32832, 1,710, Enerplus, Garter 152-94-18A-19H, Antelope, t9/17; cum 451K 11/21; cum 460K 5/22; 486K 3/24; cum 494K 2/25;
  

February 19, 2017: compare the screenshot of the map taken today with that taken at the time of the original post. Current map:

November 29, 2015: the Bull and the Rattle wells are huge!

June 17, 2015: production update for the "Ribbon" well has been posted.  

Original Post

Yesterday I mentioned that Enerplus was going to report a "monster well" today. I was wrong. Enerplus reported two "monster wells" today.

At the bottom of that post I have a screen shot and asked readers if they saw the same thing I was seeing.

Yesterday I was impressed by the fact that the immediate area in which this well was drilled has had a spectacular history with some great wells. Some wells drilled back in the late 1950s are still active (rare); and many of the wells (drilled from the late 50's) have/had a total production of almost 1 million bbls of oil, many from two payzones, the Madison and the Sanish. 

In the big scheme of things (look at the Grail, the Truax, the Parshall, the Banks, the Sanish, etc) this area has hardly been touched with horizontal wells. (Compare the Truax screen shot at the very bottom of this post.)

But now that I've seen the file report, this well has even more surprises. 

First two screen shots.

The first screen shot provides an overview of the general area:

The second screen is a "zoom in" of the four Enerplus wells, two of which reported results today:

The wells of interest:

• 4240, PA/AB/391/25/45, Hess, AMU H-517HR (a re-entry well), Devonian/Sanish/Madison, t5/67; t7/91; t10/06; cum 206K (6/91); 3K (5/05); 75K (12/16); as far as I can tell, never fracked; went inactive on/about 4/14; back on active status 6/15; inactive 8/17;
• 18435, 2,376, XTO, Nelson Federal 41X-5G, Antelope-Sanish pool, 11 stages; 1.3 million lbs sand/ceramic; t3/11; cum 337K 3/20; went inactive 5/15; back on status 1/16; off line 10/18; back on line 4/19; cum 390K 11/21; cum 400K 5/22; cum 416K 3/23; cum 431K 3/24; cum 441K 2/25;
  
• 24337, 2,519, EOG, Hawkeye 3-2413H, Antelope-Sanish pool (all EOG paperwork says "Bakken" but "Sanish" is inked in on most recent sundry form -- this is a Sanish pool well); 28 stages; 9.7 million lbs sand; t5/13; cum 817K 3/20; cum 872K 11/21; cum 891K 5/22;  cum 921K 3/23; cum 950K 3/24; cum 970K 2/25;
• 26737, 3,374, Enerplus, Ribbon 152-94-18B-19H, Antelope-Sanish, again, much of the paperwork says "Bakken," and the target was clearly the middle Bakken (middle Bakken "C") but the scout ticket says the Sanish pool; 42 days (316 hours) of drilling; 42 stages; 10.0 million lbs sand; t4/14; cum 650K 3/20; cum 667K 11/21; cum 674K 5/22; cum 681K 3/23; cum 688K 3/24; cum 692K 2/25;
  
• 26990, 3,102, Enerplus, Hognose 152-94-18B-19H-TF, Antelope-Sanish, specifically Three Forks 2nd bench, three laterals; 60 days (533 hours) drilling, 41 stages; 9.7 million lbs sand; t4/14; cum 573K 3/20; cum 598K 11/21; cum 605K 5/22; cum 611K 3/23; cum 618K 3/24; cum 623K 10/24; offline;
  

• 26990, Hognose 152-94-18B-19H-TF
• Hognose 152-94-18B-19H-TF-ST1
• Hognose 152-94-18B-19H-TF-ST2

• 26988, 2,842, Enerplus, Bull 152-94-18B-19H-TF, Antelope-Sanish, t6/15; cum 557K 3/20; off line 3/20; back on line 5/20; cum 588K 11/21; cum 620K 3/23; cum 642K 3/24; cum 664K 2/25;
  
• 26989, 2,357, Enerplus, Rattle 152-94-18B-19H, Antelope-Sanish, t6/15; cum 418K 3/20; off line 3/20; back on line 6/20; cum 438K 11/21; cum 450K 3/23; cum 457K 3/24; cum 464K 10/24; recently off line; coming back online.
  

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Formation tops / stratigraphy for the Ribbon well (#26737):

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Formation tops / stratigraphy for the Hognose well (#26990):

Note the markers, "A" through "E" for the middle Bakken. I've seen these markers in other well reports. Note the thickness of the middle Bakken, TVD (10,359 - 10,318 feet = 41 feet).

On the log reports, the formation tops (TVD):

• lower Bakken shale: 10,359 feet
• Three Forks - 1st bench: 10,383 feet
• Three Forks "RT": 10,419 feet
• Three Forks - 2nd bench: 10,431 feet

Three Forks thickness, 1st bench: 36 feet

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For The Archives

Compare the development of the area of the Antelope oil field (noted above) with the development of a small area of the Truax oil field -- this is what surprised me most by the snake wells announced today. This screen shot taken the same day as the other screen shots above:

Bakken 101 -- Stratrigraphy Of The Bakken Pool

For newbies: this is a screen shot from Whiting's corporate presentation, November, 2013.

I believe I have posted this screen shot previously; if not, I have certainly discussed it. Not all pay zones are in every area of the North Dakota Bakken.

The Scallion is sometimes referred to as the "false Bakken." See first comment below.

Note: The slide does not delineate the upper Three Forks and the lower Three Forks. The vast majority of "Three Forks" wells in North Dakota targeted the upper Three Forks. Only a handful of wells (CLR, KOG) have tested the 2nd, 3rd, and 4th benches of the lower Three Forks.

Be sure to double-click on the screen-shot to open it in another window. Note the millions of barrels of original oil in place per 1280-acre spacing unit. The recovery rate from the Bakken Pool is variously reported from 1% to 8%.