Devon Energy Corp.'s experiments in Oklahoma's stacked reservoirs continue to fulfill expectations, with a third Meramec spacing pilot completed and 10 more pilots planned through the end of the year.
In the latest pilot project, dubbed the Pump House, Devon used a seven-well pattern across a single-section interval of the upper Meramec in Kingfisher County. Initial production results over 15 days averaged 2,200 boe/d per well (55% oil) at a cost of $6 million each, the Oklahoma City-based independent said.
The Meramec, within the Sooner Trend of the Anadarko Basin, mostly in Kingfisher and Canadian counties -- i.e. the STACK -- continues to entice Midcontinent players, and for good reason, said COO Tony Vaughn.
"Results from our initial three Meramec spacing tests are outstanding, with flow rates exceeding type-curve expectations and minimal interference between wells," he said. "These positive results indicate the potential for tighter spacing and increased inventory in the core of the over-pressured oil window.
"We continue to advance several additional Meramec spacing tests that will help us accelerate learnings and further prepare for full-field development in 2017 across our industry-leading position in the STACK."
The Pump House wells, drilled with 4,700-foot laterals, used a completion design that deployed 2,200 pounds of proppant/lateral foot across 35 fracture stages. Perforation clusters were spaced 25 feet apart. To manage pressure and maximize value, the wells were brought online using an engineered choke management approach starting at a 14/64-inch choke and gradually increasing to a 26/64-inch choke over 15 days.
The Pump House pilot is adjacent to Devon's Born Free pilot and three miles north of the Alma pilot (see Shale Daily, July 19). Production from the two-well Born Free pilot announced earlier this year "continues to perform exceptionally well, averaging a 120-day rate of 1,400 boe/d per well. The five-well Alma pilot has achieved a 60-day average rate of 1,300 boe/d on a per well basis."
To determine the optimal spacing approach for the stacked-pay intervals in the Meramec, Devon plans to take part in more than 10 additional spacing pilots to the end of this year. The pilots are focused in the over-pressured oil window, with tests conducted for up to eight wells in a single Meramec interval.
Devon is evaluating whether to jointly develop multiple stacked-pay intervals through staggered well pilots. Initial production rates are expected in the next few months.
Two extended-reach Meramec wells recently were brought online in eastern Blaine County, which is within the core of the STACK. Devon's Marmot 19-1HX and Blue Ox 3130-4AH were drilled with 10,000-foot laterals and achieved average peak 24-hour rates of 3,700 boe/d per well, 70% oil-weighted.
Marmot and Blue Ox's larger completion design deployed 2,600 pounds of proppant/lateral foot across 50 fracture stages with perforation clusters spaced 30 feet apart. Peak 24-hour rates were achieved with a 28/64 choke.
"As we progress to full-field development in 2017, it is our expectation that we will develop the majority of our stacked-pay Meramec position with extended-reach laterals, which will significantly increase rates of return from this world-class reservoir," Vaughn said.
Devon is planning to raise as many as four operated rigs in the STACK through the last half of the year, which could bring its operated rig count to six. Because of the increased activity, $450 million has been earmarked for STACK activity this year, a 40% uptick from previous guidance.