Thursday, December 15, 2011

The Bull's Eye, Bakken -- A Bit of Rambling -- Duperow Formation -- The Bakken, North Dakota, USA

The Parshall oil field, back in 2007, got us all excited about the Bakken. Then, Whiting showed the potential of the Bakken with the Sanish oil field just to west of EOG's Parshall oil field.

The KOG acreage in the reservation was the next to take off, delayed a bit due to bureaucratic delays at the federal level. 2010. 

Then we had the BEXP breakout northwest of Williston. 2010-time frame if I remember.

Then, somewhat simultaneously, we had Whiting develop its southern ops.

In 2011, folks started talking about the Bakken "manufacturing" phase. It's my impression that if we are in the "manufacturing" phase, "we" are entering it in fits and starts. I'm still seeing a lot of "new," albeit de-risked, areas being targeted. For me the manufacturing phase will be here when we see nothing but multi-well pad permits, and the spectre of the EPA banning fracking is a distant memory. We are still getting mostly individual wells, including a fair number of wildcats; if you can believe that, this late in the Bakken boom, still getting wildcats. I see about six permits for wildcats in the Williston Basin every week, it seems. 

Over the past year or so, I started to notice activity and excitement moving to northeast McKenzie County, and going back to early presentations of the Bakken, it certainly looks like this area may end up being the hottest spot in the Bakken.

After today's daily activity report came out, I looked at two of the fields reporting good wells, the Timber Creek, and the Westberg, both in the bull's eye.

While touring the GIS map server I saw the Charlson field, forgetting that this field was also in the bull's eye. With its history of great wells, it all makes sense. Just out of curiosity, I took a look at a very old well that is still producing in the Charlson:
  • 5727, 675, Denbury Onshore, Federal 33-1, Devonian pool; Charlson; s10/75; t12/75; cum 902K 10/11, and still producing 1,500 bbls/month. This well was an absolute gusher when it first came on-line, equal to the best Bakken wells. It had a typical Bakken decline but then stabilized, but early this year it looked like it was going to dry up. But they must have gone in with a work-over rig back in the spring/summer, because it went from 53 bbls over three months (Jan - Mar, 2011) to 1,426 bbls in October, the most recent month for which we have data. 
A million bbls of oil. Spudded in 1975, and still producing 36 years later.

Geologic Trivia

Based on the well file, it appears the Duperow formation was the target formation. See first comment below. In my haste I had equated the Duperow with the Devonian (two completely different "things": the Duperow a geologic formation; the Devonian, a geologic time period). At the time this well was spudded, it appears folks were using the terms interchangeably, even though a number of formations were laid down during the Devonian Period.  For example, the Three Forks formation was laid down during the Devonian Pool, but now the Three Forks is administratively tied to the Bakken Pool. (In the 1970s, the Three Forks was a non-payzone, like the Bakken, because the technology had not been developed to unleash tight formations. So, at that time, no one would have been talking about the Three Forks as part of the Devonian Pool.)

The Duperow is deeper than the Bakken, Three Forks, and the Birdbear. Prior to the current boom:
The Duperow Formation produces from stratigraphic traps in the central Williston Basin, from structural traps along the Nesson anticline, and from combination traps on the Billings anticline....The Duperow Formation is the third largest oil producing zone in the state, after the Madison Group and the Red River Formation, and produces a combination of oil and natural gas (Fig. 19).
My hunch is that a lot folks were using "Devonian" and "Duperow" interchangeably at the time this well was spud, much as folks use the Bakken colloquially to describe the current boom, even though the Three Forks is now known to be part of the Bakken boom.


  1. FYI - The Devonian is not really another name for the Duperow - the Duperow is a formation of Devonian age. Other Devonian formations in the Williston Basin are the Three Forks, Birdbear (aka "Nisku"), Souris River, Dawson Bay and Winnipegosis. The Bakken formation straddles the Mississippian and Devonian time periods.

  2. The names and concepts are tricky. Even different E&P companies use different names for the same formations.

    In the Permian (Basin, not era), the Approach Resources presentation has a visual with the various names used by different companies for the formations they explore. It is helpful. The WB language seems to be relatively standard, but the Mississippian is in ND, TX, OK, KN, etc. so it isn't exactly intuitive.

    Maybe Dickinson State should be renamed Mississippian State, just for the fun of it.

    BTW, Frac Tech has some news brewing. Selling sand to Saudi Arabia? Well ... stay tuned.

    anon 1

  3. That has been one of the rewarding things about the blog: learning the jargon. I make a lot of basic mistakes, but getting corrected helps me remember.

    My hunch is that a lot of folks learn from my errors. Smile.

    I get a kick out of how some folks read things very, very closely. I'm more of a "concept" person; get the general idea; not good with details.

    Fracking in Saudi, huh?