Bakken Formation Urban Legends

1. Oil shales are mined not drilled! —WRONG!

Unfortunately, I have seen this stated about the Bakken more than once. Why? Some people have just enough knowledge to be dangerous. There are oil shales that can be mined. However, the Bakken formation does not fit this category. The Bakken is thousands of feet underground, and contains mature “sweet crude”. In contrast, shallow mineable oil shales contain kerogen which does not easily flow, and may appear waxy or have similar properties grease or tar. There is a window of heat and pressure that is favorable for oil to mature (Oil window ca. 60°-120°C, gas window ca.120°-150°C). Mineable oil shales typically missed at least one part of the oil formation process.

In some cases it is possible that bacteria degraded the oil in shallow oil shales, but biological degradation is more common in tar sands, and is not typically used as an explanation for oil shales.

If you want to know more about mineable oil shales.

Read the two web pages first.

http://www.npc.org/Study_Topic_Papers/27-TTG-Oil-Shales.pdf

http://ostseis.anl.gov/guide/oilshale/

Then watch this video, and keep in mind that oil shale mining is a water intensive process, and the formation happens to be in a very arid region of the United States.

2. The cost of extracting oil from shale is prohibitive.

Again, this myth often falls back to people not understanding that the Bakken is a deep formation and is not mineable.

There are no outcrops of the Bakken, and it is only accessible through drilled oil wells. Typically, Bakken wells have at least one horizontal leg, and the Middle Member of the Bakken is the target unit because fluid can flow through the middle member much better than the upper and lower members (orders of magnitude). Drilling Bakken wells is expensive, and it often costs more than 5 million dollars per well. However, the current drilling boom in North Dakota should speak for itself. The majority of the drilling in North Dakota is focused on the Bakken, and it is expected to continue into the foreseeable future.

As of today there are 96 Rigs drilling in North Dakota. Last year at this time there were around 70. In 2007 there were over 120. The drop was a result of the stock market and energy crash.

In order to make the Bakken wells economically viable I have seen figures that oil prices needs to be anywhere between $30 and $70 a barrel to be profitable.

Economic data is hard to come by if you have read anything good let me know.

3. There are 400 Billion barrels of oil recoverable in the Bakken.

Sorry…

Supposedly Richard Pollastro, Bakken Formation task leader at the USGS, said the myth stemmed from a 1999 draft report. Which may or may not be true.

The specific draft report is the Leigh Price Paper: Potential Resources in the Bakken Formation which was release by the EERC after Price’s death. The USGS refused to officially release the draft.

The misconception was common in 2008, but I still see it posted from time to time. A few weeks before the USGS released their updated estimates for recoverable oil in the Bakken. Several media outlets and hundreds of bloggers saw very large OOIP numbers like “400 billion bbl OOIP” in documentation that was written for people with a background in geology. Unfortunately, they did not know that “OOIP” is an abbreviation for Original Oil in Place which means that the geological formation had the potential to generate 400 billions barrels of crude oil. Just because Bakken had the potential to generate the oil does not mean that we can retrieve it. The oil may have even migrated out of the formation which can be difficult to track. Currently the Bakken is expected to give up 2 to 5 percent of the original oil in place (OOIP). Regardless of the OOIP the USGS’s estimate for actual recoverable oil is around 3.65 billion barrels with current technology.

From what I read some industry leaders think that number is very low. Future recover rates will likely be improved by advances in technology, but it is not something to rely on. Even in the best case the recoverable oil from the Bakken will probably be less than 10%. Why? Porosity an permeability are extremely low and even though the oil is there it is unable to flow to the well. It is very difficult to fix something that is more than 8000 feet below ground.

4. Original Oil in Place “OOIP” numbers are all over the place geologists are full of crap!

True! In reality OOIP numbers have ranged from 900 to 200 billion bbl depending on which calculation method you choose to go with. The number is calculated using organic content, volume, and thermal maturity.

There is a lot of variation because several different people have calculated the amount of oil in the Bakken. The following are some reasons for the deviation.

– Some people like big numbers 🙂

– Knowledge of organic content has been better mapped.

– Thermal maturity may have been ignored in some calculations

– The volume may have been poorly constrained. (Geographic area)

– What we thought we knew about thermal maturity has recently been turned on its head because the thermal gradient may have been improperly calculated for the large portions of the North American continent. (How fast it gets hot as you go down) Basically thermal gradient was calculated using water wells in the northern portion of the United States. Unfortunately, water wells can be affected by surface climate, and the last glaciation put a strong signal into the upper portion of the earth’s crust which skewed the results in the thermal gradient calculation. What this all means is that a much larger area of the Williston Basin is likely thermally mature than previously thought.

http://www.wbpc.ca/assets/File/Bios%20and%20Presentations/8_Gosnold.pdf

http://www.bsc.nodak.edu/gpee/presentations09/WilliamGosnold.pdf

Expect to see some updates or related posts on this subject in the future.

If you would like to be extra nerdy you can read this. Everything through about page 50 is background information on the Bakken. (Not focused on Petroleum)
Huber, T. P. 1986. Conodont biostratigraphy of the Bakken Formation and
lower Lodgepole Formations (Devonian and Mississippian), Williston
Basin, North Dakota. Unpublished Masters thesis, University of North
Dakota, Grand Forks, N.D.

This is probably the only OCRed copy in existence. Any grammatical errors are probably a result of the OCR process. Let me know if you find any major mistakes.

Filed under: BakkenEnergyFrackingInvesting

Like this post? Subscribe to my RSS feed and get loads more!