When the number of wells begins to saturate a field, folks will start talking about "unitization," which Schlumberger defines as the combining of multiple wells to produce from a specified reservoir.
Others associate unitization with enhanced oil production (maybe that is implied in the Schlumberger definition). "Unitization is similar to pooling, but it occurs when producer(s) are ready to use enhanced oil recovery to maximize production from a common reservoir. Sixty percent of royalty owners (weighted) must agree to unitization before the NDIC will authorize it." One can find requests for unitization in non-Bakken formations in North Dakota in the hearing dockets.
Terms associated with "unitization" include pressure maintenance, secondary recovery, and tertiary or enhanced oil recovery (EOR). Wikipedia has a nice overview. It is interesting to note the differences in definitions of these terms at the various sites. Those sites will take you to discussions of waterflooding and enhanced oil recovery (particularly the use of CO2 to increase oil production) Denbury is one of the leaders in EOR; it bought Encore (back in 2009/2010) which is active in North Dakota.
Because of the nature of the geology of the North Dakota Bakken, there are folks that argue the ND Bakken is not amenable to waterflooding or enhanced oil recovery. That is yet to be determined. Theoretical articles support the contention that unitization won't work in the ND Bakken, but theoretical arguments several years ago also suggested that the ND Bakken was not economically viable.
Farther west, in the Alberta Basin Bakken, "they" have begun exploring enhanced oil recovery techniques. Specifically, Crescent Point is looking to use enhanced oil recovery techniques in the Alberta Bakken.
Having locked up a dominant land position in both the [Alberta] Bakken and Lower Shaunavon plays in Saskatchewan, Crescent Point Energy Corp. hopes to more than double its reserves with further exploitation and enhanced recovery.The company believes it could more than double their current reserves over the next three to five years, just through infill drilling, waterflood implementation and production optimization. EOR and production optimization could provide an additional 5,000 drilling locations and the potential to add over 500 million bbls of reserves. [This section corrected April 3, 2011; see comment section.]
[According to its CEO], Crescent Point is well positioned to further exploit two of Western Canada's hottest plays.
As noted above, some argue that waterflooding won't work in "tight formations" like the Alberta Bakken or the North Dakota Bakken. Experts acknowledge that but Crescent Point is going to try.
For now, in the North Dakota Bakken, we're going to see increasing emphasis on infill / increased density wells. Take a look at what Whiting is doing in the Sanish. Look at BEXP's February corporate presentation with a relatively new wrinkle: increased emphasis on infill wells in their Ross Prospect and their Rough Rider Prospect (slides 16 and 18). Producers talk of "pilot" wells to see if spacing units can support additional wells.
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Connecting some dots regarding CO2 injection in the North Dakota Bakken.
EOG's #16713, Austin 1-02H: EOG requested and was given permission to test CO2 injection back in 2008.
Background of Austin 1-02H
- Short lateral in the prolific Parshall oil field, section 2-T154N-R90W
- Spudded December 13, 2007
- IP: 781 bbls
- A monster well, as many are in the Parshall: > 222K in first 10 months, prior to CO2 injection
- CO2 injected for 11 days; half in September; half in October
- Wells monitored in the immediate 2-mile radius to see if CO2 was breaking through (communicating) with other wells; CO2 was detected in one well a mile away; not immediately detected at two other wells about same distance away.
- I found it interesting that one of the wells where CO2 was not detected, had a significant increase in monthly production following the injection; it may have just been coincidence (Bruhn 1-12H, #17128, a non-EOG well).
- To date: this well has produced a total of 416K bbls of oil; most recently it is producing 4,000 to 5,000 bbls/month
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Oil companys do not have to pay lease bonus to hold mineral leases? See ND Supreme court case.
ReplyDeleteIrish Oil & Gas, Inc. v. Riemer
Can anyone tell me What this is?
I was unable to find the Supreme Court ruling on this one. I found the appeal but I don't know how it ultimately ended up. I don't know if many folks read the comments on my blog.
ReplyDeleteYou may also want to ask the question over on the Bakken Shale Discussion Group, linked on the sidebar at the right.
http://groups.google.com/group/bakken-shale-discussion
"Up north, in Alberta, "they" have begun exploring enhanced oil recovery techniques. Specifically, Crescent Point is looking to use enhanced oil recovery techniques in the Alberta Bakken."
ReplyDeleteThat is the Saskatchewan Bakken not the "Alberta Bakken". The Alberta Bakken or the Alberta Basin Bakken is a misnomer given by Rosetta Resources for a group of formations that includes the Lower Banff, Exshaw Shale and the Big Valley. The Exshaw Shale in the Alberta Basin(the basin extends from Alberta to northwestern Montana) is roughly the same age as the Bakken of Williston Basin is(early Mississippian/ late Devonian) and so it can be considered to be an age equivalent to the WB Bakken. Only a handfull of wells have drilled into the Alberta Basin Bakken and it's not certain yet if it's even a commercial resource.
Crescent Point's Bakken waterfloods are in the Williston Basin Bakken in Saskatchewan.
It is obvious I have made a huge mistake with regard to the "true" Alberta Bakken. I have confirmed the veracity of your comment at several other websites. Thank you.
ReplyDeleteI obviously have a huge gap in my understanding of the Alberta Bakken and have much work to do to correct it. It will take a day or so to correct all my entries regarding the Alberta Bakken. I am extremely sorry to have caused so much confusion.
Three questions:
1. Do you understand the difference between "cement liners" and the "Packers system" as it pertains to waterflooding, or could direct me to websites that discuss the issue.
2. Are waterflooding and fracturing mutually exclusive? In other words, did Crescent Point frack their Williston Basin Bakken wells in Saskatchewan or did they go directly to water flooding?
3. I am still confused with regard to our statements regarding Rosetta Resources. According to quick search on the net, Rosetta Resources is also involved in the "true" Alberta Bakken (similar to the WB Bakken) as you describe. Is Rosetta Resources in Montana also targeting another formation, which has been incorrectly labeled the "Alberta Bakken"?
Again, thank you very much for clarifying the Alberta Basin Bakken.
ReplyDeleteI have updated my original post; hopefully it's more accurate.