Abstract
Calculations of OIP, oil and water volume production, and formation recovery factor are problematic in Unconventional Reservoirs, which includes the Bakken-Three Forks reservoir complex. This study was designed to use specialized well logs and core to determine: 1) PHIT and PHIE, 2)variations in water and oil volumes, 3) pore size distribution, 4) in-situ oil viscosity, 5) wettability, and 6) free vs. clay bound water throughout the oil-bearing intervals in the Middle Bakken and Three Forks.
A pilot well was drilled, cored, and logged in the Bakken formation in from the lower Mississippian Lodgepole through the upper Permian Three Forks. A complete logging suite was run including a dielectric and NMR log. Along with conventional core analysis (P&P, XRD), preserved core plugs were analyzed with a 20MHz NMR spectrometer both as-received and after they were saturated with decane (C10). This allowed for the location of the oil T1 and T2 signal before any possible alteration of the rock wettability resulting from cleaning. Using the measured clay-bound water (VCBW) from the NMR, a dual water CRIM dielectric inversion water volume model was developed that compensates for the difference between the salinities of the connate water and the clay-bound water. In the case of the Bakken, these differ by more than an order of magnitude.
Mapping of the NMR data in T1T2 space as well as T2 intrinsic-Diffusion (T2D) space allowed for the analysis of variations in water and oil volumes, pore size, oil viscosity, wettability, and free vs. clay bound water. Results of the analysis are shown for each formation from the Lodgepole down through the bottom of the Three Forks. Analysis shows intervals with free water in the larger pores and confirms that wettability is a function of carbonate content. The Baker dielectric tool that was used transmits five frequencies, which gives five depths of investigation within the 1-4 inch range of the NMR activation depths. A combination of the two data sets identifies the OBM filtrate on the T2D maps.
This analysis became very instructive in our understanding of water sources associated with fluid production. Since the various formations are often mixed wet or oil-wet, 1) water becomes the mobile phase and 2) formation recovery factor decreases. Water volume in the rock matrix can be determined by either the NMR or dielectric models totally independent of the Archie exponents m and n, which is important in understanding Unconventional Reservoirs where Rw, m, and n are constantly changing.
Speaker Biography
Dick Merkel is President of Denver Petrophysics LLC, which is a consulting firm dedicated to developing logging analytical techniques for petrophysical models tied to core, completion, and production data in complex reservoirs. For the past thirty years, the emphasis of his work has been on the rock physics of NMR and dielectric log combined with core measurements.
Previously, Dick worked at Encana and Newfield where he worked on teams that developed reservoir models for conventional and unconventional oil and gas reservoirs in the Rocky Mountains. Prior to its closing in 2000, Dick was a Senior Technical Consultant at Marathon Oil Company’s Petroleum Technology Center in Littleton, CO where he worked on evaluating new logging tools and technology and developing techniques for their application in Marathon’s reservoirs worldwide.
Dick Merkel has been on the faculty at The Pennsylvania State University and the Colorado School of Mines where he has taught courses in petrophysics, signal processing, and earth physics. He holds a BS in physics from St. Lawrence University and a MS and Ph.D. in geophysics from Penn State. He is a past president of SPWLA, the SPWLA Foundation, and DWLS. He is currently a member of SPWLA, SPE, and SCA.
|
|
Regular luncheon reservation: 
Vegetarian luncheon reservation:
Use one of the PayPal links above to make your luncheon reservation.
If you are registering for someone else or using a PayPal account that is not in your name, please click here to send us an email with the correct registrant information. You should also use this link if you are registering multiple people; please provide the name and company affiliation for each registrant.
Forward this newsletter to a friend to invite them to the luncheon.
|
|
|
|
|
|
From the President
Yulia Faulkner
Dear DWLS members and friends, welcome to the 2021-2022 Denver Well Logging Society new year. This will be my second year as a President of DWLS and I am looking forward to having a great year filled with technical talks, workshops, and in-person luncheons. Yes, we are going back to having luncheons in person. Wynkoop has welcomed DWLS back and we are happy to announce first DWLS September luncheon will be on Sept 21st at the Mercantile room (note this is upstairs in the Wynkoop; the old room is no longer available for meetings). DWLS board is looking forward to seeing you all!
I would also like to thank new and past members of the board for volunteering and spreading the DWLS spirit within the Oil and Gas industry, professional communities, and our universities. Many thanks for the commitment to the DWLS!
I will look forward to continuing advancements in Petrophysics in 2021-2022. There is still a lot to learn, and I feel excited for what may come. I am also looking forward to seeing improvements and stability within Oil and Gas industry, we all need it. Please continue to support and keep in touch with peers.
As always, if you have ideas about how to improve DWLS, please reach out.
|
|
|
|
From the VP - Technology
Jenny LaGesse
Hello again and welcome to the 2021-2022 season of the DWLS technical luncheon series. We hope you had a healthy summer and are ready to dive into our first fall talks. The big news: we’re moving away from virtual luncheons and going back to holding meetings at the Wynkoop Brewery. We will be in a different room at the Wynkoop than in previous years, but we are looking forward to being with our colleagues and friends again in-person. Pro: beers with friends while discussing petrophysics back downtown! Con: no more pajamas while discussing petrophysics on the couch.
This season our goals are first to proceed with safe and healthy luncheons. In accordance with CDC guidelines for large groups, we ask that unvaccinated attendees wear a mask when not enjoying their lunch during our meetings, and that if you feel unwell you do not attend. As the CDC suggests, we encourage but will not require all members regardless of vaccination status to wear masks to slow transmission, particularly during these upcoming winter months. (Considerations for Events and Gatherings | CDC)
Following that, our goals are to provide relevant and interesting speakers and topics to the Denver well logging community. If you would like to be a speaker or have suggestions for luncheon topics, please send them along to: VP_Technology@dwls.spwla.org.
We’re opening our first meeting Tuesday, September 21, at 11 am with a familiar face: Dick Merkel of Denver Petrophysics, LLC. His talk is titled: “Petrophysics in Unconventional Reservoirs; Example of Log and Core NMR T1-T2 and T2-D Mapping of the Bakken Reservoir.” You can register online.
In the months to come our luncheons will feature:
- Chad Hartman, Stratum
- Gama Firdaus, CSM
- Patrick Hayes, GeoStar
- Patricia Rodrigues, SeisPetro and Strategic Decisions Group
Stay tuned for more details regarding scheduling.
There will not be a joint DWLS-RMAG Fall Symposium this year due to the pandemic. We are setting our sights on Fall 2022. If you have any suggestions for topics for that event, or for the Spring 2021 DWLS Workshop, please send your thoughts to: VP_Technology@dwls.spwla.org.
Looking forward to seeing you all this September at the Wynkoop!
|
|
|
Calendar of Events
Click the calendar to the right to view events on the web.
Other Important Events
2022 SPWLA Annual Symposium, June 12-15, 2022 (Stavanger, Norway)
|
|
DWLS Sponsors
Click here to view the sponsors on the website, or click on any image to contact a sponsor.
|
|
Chapter Statistics
Statistic
|
This Year
|
3-Year Average
|
| # of Active members * |
235 |
314 |
| # that are New members |
1 |
15 |
| # that are Students * |
7 |
7 |
| # that are Lifetime Members * |
260 |
261 |
| September luncheon meeting attendance |
|
46 |
| October luncheon meeting attendance |
|
37 |
| November luncheon meeting attendance |
|
28 |
| Holiday party attendance |
|
38 |
| January luncheon meeting attendance |
|
43 |
| February luncheon meeting attendance |
|
54 |
| March luncheon meeting attendance |
|
38** |
| April luncheon meeting attendance |
|
43** |
| May luncheon meeting attendance |
|
48 |
* Note that we did a thorough cleanup of bad email addresses that resulted in some of our members being removed until they can be tracked down again. So this year's membership numbers are going to be a bit lower.
** These numbers are skewed due to COVID-19 luncheon cancellations.
|
|
|
|
The DWLS Newsletter is published monthly September through June by the Denver Well Logging Society. For information on membership or advertising, contact the editor. For other inquiries, contact a member of the Board of Directors.
|
|
|
|
|
