Case Studies

A Mighty Viking Indeed: 2/12-35-55-22W5 Viking Gas

Peyto’s only Viking well of 2020 was horizontal 2/12-35-55-22W5,  spudded  in  August  at  the  east end of the Wild River Field (figure 1), where the  company  is  known  more  for  its  Spirit  River  and  Cardium  development.  With  an  IPmax  of  2,510  boepd  (15.0  mmcf/d  gas),  2/12-35  was  Peyto’s best well of the year. It had the highest gas rate of any non-Montney or Spirit River well drilled in 2020, and one of the highest Viking gas rates ever recorded. While essentially no liquids from 2/12-35 have been reported in the public domain  (98  bbls  of  condensate  to  date),  it  can  be assumed that actual liquids yield, as per most area operators, is higher.

Geology

At  Wild  River,  the  Viking  is  within  the  Deep  Basin  pressure  regime  and  gas-rich.  Based  on  its licence, downhole survey and offset well logs, the 2/12-35 well is targeting the upper portion of a 15m thick coarsening-upward unit within the Viking  Formation  (figure  2).  This  unit,  with  log  porosity (sandstone matrix) ranging from 2 to 6%, represents  a  prograding  shoreface  cycle  within  a highstand systems tract (Reinson et al., 1994). This unit is mappable throughout the subject area as  the  “Viking  Sand”  (figure  3),  and  comprises several smaller scale (1–5m) stacked coarsening upward successions, indicative of fluctuating sea levels during deposition. Southeast of 2/12-35, in parts of Sundance, the Viking was deposited as incised valley fill (figure 3). These  estuarine  deposits  host  wells  that  once  produced  at  rates  exceeding  that  of  2/12-35,  and are now utilized for gas storage. Peyto’s Big Sunny gas storage unit is an example (figure 1) (Peyto, 2021).

The Wild River Viking: Now with Horizontals!

The Viking first yielded gas at Wild River in the early 1980s. Drilling peaked in the early 2000s, but  the  Viking  remains  undeveloped  in  much  of the area (figure 1). Wild River Viking gas has typically been produced commingled in vertical wells with zones such as the Cardium, Dunvegan, Spirit River, Bluesky and Cadomin. Notwithstand-ing a short lateral (<200m length) drilled by CNRL in 1994, Peyto drilled the first horizontal Viking well in the area in December 2017, immediately southwest of 2/12-35 at 8-34-55-22W5 (figure 1). This well came on production at 1,071 boepd (6.4 mmcf/d). Peyto’s 2/12-35 was the area’s second Viking horizontal well.

So Why Is the New Well So Much Better?

There  are  no  obvious  differences  in  Viking  log  properties from available wells that would explain 2/12-35 coming on at a rate over twice as high as that of 8-34 (figures 3 and 4). Both wells are located  on  the  edge  of  a  Leduc  reef  structure  (figure  1),  where  structural  drape  features  and  differential compaction can enhance porosity and permeability. However,  one may expect both wells to be affected similarly.

Some notable completions differences between the two wells are shown in table 1. The 2/12-35 well used a markedly higher intensity completion based on the number of stages and volume of fluid used. Because the 2/12-35 well is on confidential status until August 2021, other data such as the amount of proppant used are currently unavailable.

But Is It a Real Viking, and Not Just a Misunderstood Noti Hipster?

Peyto’s SECOND highest IPmax of 2020 (1,577 boepd, or 9.5 mmcf/d) is from a well targeting a Notikewin channel at 2/4-1-56-22W5, directly northeast of the 2/12-35 well (figures 1 and 3). Well logs indicate that this channel lies just below the  base  of  the  Viking  sandstone  targeted  by  2/12-35, separated by a thin Joli Fou shale interval (figure 3). While geo-steering technology would have ensured that the 2/12-35 trajectory stayed within the Viking, a hydraulic frac extending downward more than 15 or 20m may have been able to access Notikewin reservoir. This could have been further enabled by any enhanced permeability brought on by the effect of drape over the aforementioned Leduc reef.

Conclusions

Peyto’s Wild River Viking well at 2/12-35-55-22W5 had one of 2020’s highest initial gas rates, and represents a new horizontal target for the area.

References

FracFocus Chemical Disclosure Registry, 2021. Accessed February 2021. http://fracfocusdata.org/DisclosureSearch/Search.aspx

Peyto Exploration and Development, 2021. Corporate Presentation January 2021. Accessed February 2021. http://www.peyto.com/Files/Presentations/2021/2021Jan8CorpPres.pdf

Reinson, G.E., Warters, W.J., Cox, J. and Price, P.R. 1994. Cretaceous Viking Formation of the Western Canada Sedimentary Basin. Chapter 21. In: Geological Atlas of the Western Canada Sedimentary Basin. G.D. Mossop and I. Shetsen (eds.). Canadian Society of Petroleum Geologists and Alberta Research Council, p. 353–363.

About the Author(s)

The author

Chris Podetz has been a geologist at CDL since 2017 working as an Exploration Analyst. He has written and researched over 100 articles for the Discovery Digest on a wide variety of plays and areas within the WCSB, with a current focus on the Montney, Clearwater, and Cardium. Other industry interests include lithium development potential in BC, Alberta, and Saskatchewan. Chris' previous experience includes stints as a petroleum geologist for Mapan Energy and Encana, geomechanical consulting with Advanced Geotechnology (AGI), gold exploration and resource delineation near Rankin Inlet, NU and a term as a shipper/receiver for Co-op Home Health Care in the mid-2010s. He obtained a Bachelor of Applied Science degree in Geological Engineering from Queen's University in 1997.

The author

Bio coming soon.