Preliminary Study Regarding The Middle And Lower Benches Of The Three Forks -- Geo News -- December 9, 2018

This was posted as an update to an earlier post but it is too important to be lost, so I am reposting it:

Don sent me a link to an article in the January, 2018, issue of Geo News. It should download as a pdf on your desktop:

https://www.dmr.nd.gov/ndgs/documents/newsletter/2018Winter/Examination_of_Middle_Three_Forks_Hydrocarbon_Charge_and_Production.pdf

From that article:

There is currently limited geological information available regarding the petroleum geology and economic importance of the middle to lower Three Forks.

Resource assessments of the Three Forks Formation have ranged from approximately 2 to 4 billion barrels of recoverable oil, but these assessments have been limited to the upper Three Forks (Nordeng and Helms, 2010; Gaswirth et al., 2013).

This article reports the preliminary findings of a recently initiated study on the origin and distribution of oil saturations within the middle Three Forks. It also reviews the present production footprint of 2nd bench horizontal oil wells and projects their potential future distribution.

In addition, I am examining oil saturations and hydrocarbon production in the lower Three Forks (3rd and 4th benches).

The author is Timothy O. Nesheim.

As noted, this article is a "work in progress." Unless I missed it, the author did not provide estimated reserves in the middle or lower benches of the Three Forks.

Don suggests it is likely that this paper is part of the ongoing USGS survey of the Bakken/Three Forks.

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Putting The Bakken Into Perspective -- December 9, 2018

Updates

Later, 10:07 a.m. CT: Don sent me a link to an article in the January, 2018, issue of Geo News. It should download as a pdf on your desktop:

https://www.dmr.nd.gov/ndgs/documents/newsletter/2018Winter/Examination_of_Middle_Three_Forks_Hydrocarbon_Charge_and_Production.pdf

From that article:

There is currently limited geological information available regarding the petroleum geology and economic importance of the middle to lower Three Forks.

Resource assessments of the Three Forks Formation have ranged from approximately 2 to 4 billion barrels of recoverable oil, but these assessments have been limited to the upper Three Forks (Nordeng and Helms, 2010; Gaswirth et al., 2013).

This article reports the preliminary findings of a recently initiated study on the origin and distribution of oil saturations within the middle Three Forks. It also reviews the present production footprint of 2nd bench horizontal oil wells and projects their potential future distribution.

In addition, I am examining oil saturations and hydrocarbon production in the lower Three Forks (3rd and 4th benches).

The author is Timothy O. Nesheim.

As noted, this article is a "work in progress." Unless I missed it, the author did not provide estimated reserves in the middle or lower benches of the Three Forks.

Don suggests it is likely that this paper is part of the ongoing USGS survey of the Bakken/Three Forks.

Original Post

At one million bopd, the Bakken produces (365 million bbls x 3 years =) one billion bbls every three years. Unfettered, of course, the Bakken could produce more than 2 million bopd, or one billion bbls every year and a half.

So what?

At the sidebar at the right, there is a long list with "Other Formations." Here is the link to "Norway," for example.

And from that page, the most recent post:

December 8, 2018: from Equinor's website, this date -- Johan Sverdrup—the North Sea giant Johan Sverdrup is one of the five largest oil fields on the Norwegian continental shelf.

With expected resources of between 2.1—3.1 billion barrels of oil equivalents, it will also be one of the most important industrial projects in Norway in the next 50 years. The development and operation of this enormous field will generate revenue and provide jobs for coming generations.

My hunch is that the next USGS survey of the Bakken/Three Forks will be the equivalent of adding several such fields to the Williston Basin. It is unlikely the next survey will include Three Forks B2 and B3 because so few wells have been drilled into the lower Three Forks. 

Back To The Permian -- November 17, 2016

This morning on MSNBC Morning Joe it was mentioned that the USGS analysis of the Permian showed:

• 20 billion bbls
• largest continuous reservoir USGS has ever surveyed
• 3x the size of the Bakken

I took another look at the first note at the blog regarding this new survey. At the post, the Permian:

• an estimated and previously unaccounted for 20 billion bbls crude oil
• 16 trillion cubic feet of natural gas; and, 
• 1.6 billion bbls of natural gas 

Let's go back to some earlier posts on the size of the Bakken:

• a trillion-bbl reservoir?
• Bentek: 2.2 million bopd
• USGS 2013 Bakken-Three Forks: top line estimate: 11.4 billion bbls
• Bakken production through 2040

Comments derived from those links regarding the Bakken follow.

A trillion-bbl reservoir:

• the trillion-bbl reservoir first posited by CLR, was eventually pulled back to the Leigh Price number, 500 billion bbls
• a 3% primary recovery rate of 500 billion bbls = 15 billion bbls
• a 10% primary recovery rate of 500 billion bbls = 50 billion bbls

Bentek and EIA, Bakken production 2040:

• 1.5 million bopd average through 2030; 2016 - 2030 =  15 yrs x 365 days/yr x 1.5 million bopd = 8,200 million bbls = 8 billion bbls (sub-total)
• 2.0 million bopd average, 2031 - 2040) = 10 years x 365 days/yr x 2 million bopd = 7,300 million bopd = 7 billion bbls (sub-total)
• 1 million bopd average after 2040 through unknown number of years
• total estimate based on Bentek, EIA presentations in the past: 8 billion + 7 billion + x billion = at least 15 billion bbls
• everyone pretty much agrees 3% recovery rate is a very, very conservative recovery rate for the Bakken; Whiting has suggested as much as 8%

USGS Permian and Bakken surveys

• for the Bakken-Three Forks: top-line estimate -- 11.4 billion bbls
• I've not see USGS's top-line estimate for the Permian; the headline number is 20 billion bbls
• 20 billion bbls is not 3x the size of the Bakken
• but that's about right: USGS mid-range estimate for the Bakken: 7.4 billion bbls; for the Permian: 20 billion bbls

This graphic was posted by the EIA earlier this year, August 22, 2016:

Note the amount of dark blue (Bakken) vs the Wolfcamp (blue).

In light of the new USGS survey of the Permian the graph will have to be re-done (I would suppose).

OBSERVATION 6: Random Observations Regarding the USGS 2013 Assessment of the Bakken: UND-EERC

This may or may not be trivial with regard to the USGS 2013 Assessment of the Bakken.

Check out the USGS 2013 PowerPoint presentation [The USGS Report on the Bakken] regarding the assessment of the Bakken. Slide lists the "Non-USGS Cooperators." Notably absent is UND and/or UND-EERC. The only academic entity listed is the Colorado School of Mines. Perhaps UND and UND-EERC are closely aligned with the North Dakota Geological Survey and perhaps the UND folks had some input.

Maybe I'm just super-sensitive but it certainly seems UND/UND-EERC should have been part of the process.

OBSERVATION 5: Random Observations Regarding the USGS 2013 Assessment of the Bakken: The "F95" For The Bakken Actually Decreased

The very first slide (after the introductory stuff), the USGS asks the question: why assess the Bakken  ... again? Because the "Three Forks Formation was not assessed in 2008."

There were several additional reasons, but it seems from the report that the USGS did not actually consider any of those additional reasons, based on the results (substantial increase in number of wells, longer well prouction histories, new technology, increased cooperation from industry experts, etc).

The "new" 2013 number for the Bakken Formation: 2.81 to 4.61 (mean: 3.65 billion bbls).

The  "old" 2008 assessment for the Bakken Formation: 3.0 to 4.3 (mean: 3.65 billion bbls).

Although the mean remained the same, the "F95" for the Bakken actually appears to have decreased. (This is based on the narrative for 2008 and the slide presentation for 2013, but those are the numbers provided.)

That's the observation. It's hard to believe that five years of new data, new technology, more wells, increased fracking stages/well, the assessment did not result in any change in the mean, either up or down. There are four possibilities for the Bakken mean not to have changed over five years:

a) the Bakken Formation was not reassessed; only the Three Forks
b) the oil industry has not gotten any better at recovering oil from the Bakken Formation
c) the oil industry has gotten better but the USGS took that into consideration back in 2008, and thus no change in the assessment
d) the USGS is really, really good at making estimates, and five years later, their assessments have not changed for the Bakken Formation

OBSERVATION 4: Random Observations Regarding the USGS 2013 Assessment of the Bakken: The Pronghorn Member

From the report:

The Pronghorn Member of the Bakken Formation, although geologically and stratigraphically defined as part of the Bakken Formation (LeFever and others, 2011), is assessed with the Three Forks Formation.

Where present, the Pronghorn Member is in fluid communication with the underlying Three Forks reservoirs.

Two comments:

• this is an administration decision, to include the Pronghorn Member with the underlying Three Forks reservoirs (note the plurality of reservoirs when discussing the Three Forks Formation)
• noting that the Pronghorn Member is geologically and stratigraphically defined as part of the Bakken Formation (and has been so defined at least since 2011) provides scientific basis for the NDIC's decision to redefine stratigraphic limits as requested by the oil industry

And that's it. Nothing controversial. Simply an observation and a couple of comments.

But, I cannot resist: It would be interesting to read the 2011 Julie LeFever paper that explains why the Pronghorn Member, lying below a tight shale formation, and communicating with the Three Forks Formation, is geologically and stratigraphically defined as part of the Bakken Formation; and, then, of course, why oil from the Pronghorn Member will be considered Three Forks oil.

I assume the answer to the second part of that question/statement is based on precedence and commingling. It makes sense to assess Pronghorn Member oil with the Three Forks Formation oil,  going back to hydrocarbon "fingerprints."

But the 2011 Julie LeFever paper should make interesting reading:

LeFever, J.A., LeFever, R.D., and Nordeng, S.H., 2011, Revised nomenclature for the Bakken Formation (Mississippian-Devonian), North Dakota, in Robinson, J.W., LeFever, J.A., and Gaswirth, S. B., eds., The Bakken-Three Forks Petroleum System in the Williston Basin: Denver, Colo., Rocky Mountain Association of Geologists, p. 11 - 26.

The North Dakota Geological Survey, Geologic Investigation No. 165 (GI-165) provides a very nice graphic of the three members of the Bakken, as well as five (5) members of the Three Forks. This is a must-read document: it points out that "current industry terminology refers to the member 5, 4, 2, and 1 as benches (i.e., member 5 is referred to as the "First Bench").

.... It is interesting to compare the oil saturations against the water saturations. Oil saturations are consistent through the Bakken, but tend to taper off below member 5 ("First Bench"). Correlations become especially important in the Continental Resources, Inc. -- #1-3H Debrecen well where the highest oil saturations are in the Pronghorn Member of the upper Three Forks. In contrast to the cross-sections wells, the EOG Resources, Inc. -- #2-11H Liberty has oil saturations throughout the Three Forks section.

... An abundance of fractures appear to coincide with higher water saturations in the Three Forks. The opposite is reflected by fractures in the Bakken. ... The absence of significant amounts of clay suggests that the marker bed that denotes the top of member 4 ("Second Bench") may not confine a fracture stimulation treatment as previously thought. ... A preliminary examination of the Three Forks  Formation raises some interesting questions as to how extensive is the resources, what are the controlling factors, and what constitutes the reservoir. Additional examination of new cores may answer some of the questions.

OBSERVATION 3: USGS Needs To Improve on Style: Slide 17 Legend

A better graphic -- A huge thank you to a reader; see comments. Now, why couldn't the USGS have done this in the first place? The link: http://i.imgur.com/pdRjCZc.jpg

Updates

Original Post

This post refers to the USGS PowerPoint presentation for the 2013 Assessment of the Bakken/Three Forks.  

At slide 17, the USGS provides a graphic of the relative size of the various basins of continuous oil reservoirs, such as the Bakken, in the United States, to include Alaska. If one is trying to downplay the size of the Bakken, this is pretty successful.

Each basin/locality has a green "dot" varying in size based on the size of the reservoir. The USGS uses four dots to represent four "sizes":

• less than 0.1 billion bbls
• 0.1 to 0.5 billion bbls
• 0. 5 to 2.0 billion bbls
• greater than 2.0 billion bbls

That was fine when the largest continuous reservoir, the Bakken, was estimated to be 3.6 billion barrels back in 2008. But with the new estimate, the graphic needs to be updated.

Take a look at the graphic (slide 17 at the link). There is not a whole lot of difference in the size of the green "dots" for the Permian, the Western Gulf, and the Williston Basin. In fact, a newbie glancing quickly at this one slide would not be all that impressed with how much bigger the Williston Basin is compared to the Permian or the Western Gulf based on the graphic or the size of the dots.

But then look at the numbers:

• Permian Basin (Midland-Odessa): 0. 51 billion bbls
• Alaska North Slope (Prudhoe Bay): 0.94 billion bbls
• Western Gulf (Eagle Ford) Basin: 1.73 billion bbls
• Williston (Bakken/Three Forks) Basin: 7.38 billion bbls

The Williston Basin, at 7.38 is more than 4x greater than the Western Gulf (Eagle Ford). And then, get this: the Williston Basin's continuous oil reservoir is almost 15 times larger than the Permian Basin (Midland-Odessa).  The "green dot" overlying North Dakota should be twice as big as it is.

Having said all that: my hunch is that the estimate for the Western Gulf (Eagle Ford) continuous reservoir is significantly underestimated, and will be revised upward in the next assessment.

USGS To Begin New Assessment of Bakken/Three Forks Starting October, 2011 -- Two-Year Study --

Link here (regional links break early and break often).

Interior Secretary Ken Salazar says there's "significant new geological information" and new oil drilling technologies since the government did its last study in 2008.

That assessment estimated up to 4.3 billion barrels of crude could be recovered using technology at that time. The agency called it the largest continuous oil accumulation it has ever assessed.

This will be interesting. This is where we stand now with estimates:

• USGS: 4.3 billion barrels
• Whiting: 12 billion barrels
• CLR: 24 billion barrels

The 2008 USGS survey of the Bakken Formation in North Dakota and Montana can be found here (a PDF document). When you get to the link, click on the PDF icon on the left. Note: the USGS says this survey was only of the Bakken Formation: the upper, middle and lower members.

New Survey of Non-Bakken Recoverable OIl in the Williston Basin Requested -- North Dakota, USA

The USGS accomplished two surveys in the Williston Basin in 2008.

• One survey was of the Bakken pool.
• The other survey was of the non-Bakken pool. 

The results:

• The Bakken survey, 2008: 3 to 4.3 billion barrels of recoverable oil
• The non-Bakken survey, 2008: 200 million barrels of recoverable oil

Today it is being reported that US Senator Hoeven of North Dakota is asking for the USGS to re-accomplish that non-Bakken survey of the Williston Basin.

The  USGS in its 1995 survey estimated there was 150 million bbls of recoverable oil in the Williston Basin (I am not sure if that included or did not include the Bakken pool; that was before the 2000-Bakken boom that began in Elm Coulee, Montana).

Regardless, thirteen (13) years later, in the 2008 USGS survey of the non-Bakken formations in the Williston basin, the USGS estimated there were 200 million bbls of recoverable oil in non-Bakken Williston oil basin.

The estimates between 1995 and 2008 were not all that different -- they were certainly within the same ballpark as estimates go in the oil industry. It's hard to believe that after thirteen years of new technology (particularly hydraulic fracking) and thirteen years of new data (core samples, seismic data), the estimates between 1995 and 2008 were so similar.

The recent excitement in the Tyler formation alone suggests a new survey is needed. But before the survey is accomplished, let's see a few new Tyler wells with new technology. That might help the USGS surveyors. Also, maybe we should wait to see what the Canadian drillers can do with the Bottineau County Spearfish wells.