Devon Energy Corp. has brought online another successful spacing pilot and a record-setting well, both within the over-pressured Meramec formation within Oklahoma’s prolific stacked reservoirs.

The Alma spacing pilot tested five wells per section across a single interval in the Upper Meramec formation within the Sooner Trend of of the Anadarko Basin, mostly in Canadian and Kingfisher counties, aka the STACK.

According to Devon, the pilot delivered 30-day initial production (IP) rates that averaged 1,400 boe/d per well, 60% light oil. Early flowback results also indicated “minimal interference between wells, suggesting potential for tighter spacing in the over-pressured oil window.”

The Alma wells were drilled with 5,000-foot laterals and brought online initially with a 12/64-inch, which gradually increased to a 20/64-inch choke.

In southwestern Kingfisher County, Devon also brought online the Pony Express 27-1H. The well, drilled with a 5,000-foot lateral, achieved a 30-day IP average of 2,100 boe/d. The well flowed 1,500 b/d of oil, 70% of the production mix.

“Oil productivity from the Pony Express is the highest of any Meramec well drilled to date in the play on a per lateral foot basis,” management said.

The Alma pilot and the Pony Express well “are examples of the excellent results we are achieving in the Meramec formation, which has quickly evolved into the best emerging development play in North America,” Devon COO Tony Vaughn said.

Additional spacing tests are ongoing to optimize the Meramec 2017 development plan. The STACK is Devon’s No. 1 U.S. priority this year, with net production in 1Q2016 averaging a record 91,000 boe/d, 39% higher year/year (see Shale Daily, May 4). Of Devon’s six total U.S. onshore rigs running between January and March, four were active in the STACK. The STACK combines the best attributes of the company’s positions in the Eagle Ford Shale and Permian Basin’s Delaware, CEO Dave Hager said in May.

With the Alma test, Devon now has two spacing pilots in the core of the Meramec oil window. Production from the two-well Born Free pilot, announced early this year, achieved a 90-day average IP rate of 1,500 boe/d per well, 60% weighted to oil. The Born Free pilot wells were spaced 400-feet apart and landed in two intervals in the Upper Meramec.

The next pilot Devon expects results from is the Pump House test in southwest Kingfisher County,” management said. The Pump House is testing seven wells per section in a single interval in the Upper Meramec. Initial flow rates are expected before the end of September.

To determine the optimal approach for developing stacked-pay intervals in the Meramec, Devon also is participating in several additional spacing pilots through 2016.

“The spacing pilots are focused in the over-pressured oil window and are testing up to eight wells per section in a single Meramec interval and evaluating the joint development of multiple stacked-pay intervals through staggered well pilots.”

Results from the Meramec spacing pilots “will help Devon optimize its master development plan in the over-pressured oil window, where the company expects to progress into full-field development in 2017.”

Improved drilling techniques are tapping into reservoirs today from Oklahoma’s carbonate, limestone, sand and shale in other formations, which in addition to the Meramec. Information about Oklahoma’s stacked plays are included in NGI‘s North American Shale & Resource Plays Factbook, which was updated earlier this year.