Manitok Energy Inc., Calgary, has gauged its second new pool oil discovery at Stolberg in the Alberta foothills, where it is preparing to spud the seventh well in its current program.
The second oil pool discovery has a 200 m horizontal leg and was not fracture stimulated. It is free flowing to surface at 1,340 b/d of 51° gravity oil plus associated gas. The well has recovered 19,568 bbl of oil and 8.5 MMcf of gas in 20 days.
It averaged 912 b/d of light oil and gas at 65 bbl of oil equivalent in the first 3 days and 1,214 b/d of oil and 95 boe/d of gas in the last 3 days. It is common to see production improve initially with unstimulated conventional reservoirs versus up to 40% declines in the first month of production with unconventional reservoirs, the company said.
Manitok receives a premium of $5-7/bbl to Edmonton par pricing due to the higher quality of the light oil.
When considering the results of Manitok’s Cardium oil discovery well and the company’s Stolberg
Mannville liquids-rich gas discovery well in 2011, Manitok believes that it has successfully drilled two top-tier wells in its first three foothills wells (OGJ Online, Sept. 12, 2011).
During the last 9-1/2 months, the first Stolberg well has cumulative production of 1.1 bcf of sweet, liquids-rich gas and 12,000 bbl of wellhead condensate, and its peak rate was 5.1 MMcfd. Its current rate is 3.9 MMcfd with condensate at 11 bbl/MMcf.
Manitok believes the first well ranks in the top 30 unstimulated vertical Mannville gas wells drilled in the last 20 years in Alberta.
The company has an average 64% working interest in more than 242,560 acres and considering the relatively underexploited nature of the foothills believes many conventional opportunities exist on its lands.
Two Cardium wells are on production. Manitok’s third well has a 700-m horizontal leg and was not fracture stimulated. However, due to permeable nature of the reservoir at this location, more than 300 cu m of drilling fluid was lost to the reservoir therefore requiring an extended swab back period.
As such, Manitok is equipping the well with a temporary battery for an extended production test to start in early July. To date, Manitok has swabbed back drilling mud and about 600 bbl of 44° gravity light oil. Use of the temporary battery for an extended period is to determine whether the well’s results support the decision to drill a second well from the same pad before adding a permanent battery.
Completion and testing are under way on the fifth well. The fourth and fifth wells are nearly vertical and are deviated from the same pad. Drilling data from both were encouraging. The fourth well will be tested after the fifth well has been completed and tested. The two wells totaled $5.2 million, considerably less than a horizontal well.
Manitok has drilled the sixth Cardium oil well in the program, a horizontal well on the same section offsetting the second new pool discovery well. Initial data are encouraging with strong oil shows during the horizontal penetration. Manitok is skidding the rig to drill the seventh well from the same pad and expects to spud by mid-June.
Manitok believes that during the last 25 years only one unstimulated Cardium oil well in Alberta has averaged more than 1,000 b/d in the first 30 days and that only about 35 unstimulated oil wells in Alberta have exceeded 1,000 b/d in the first 30 days from any formation. And a well in the Cardium oil pool northwest of Manitok’s discovery well achieved a peak rate of 340 b/d, has cumulative production of 494,000 bbl of light oil in the last 9 years, and still averages 100 b/d.