FAQ

The nomenclature for the STACK and SCOOP plays was derived from geographical, opposed to geological, acronyms. The STACK Play stands for “Sooner Trend (oil field, Anadarko (basin), Canadian and Kingfisher (counties).” The SCOOP play stands for “south-central Oklahoma oil province.” Another notable Oklahoma shale play that is often associated with the STACK and SCOOP plays is the SoHot Play. This play, too, is a geographic-based acronym standing for “Southern Oklahoma Hoxbar Oil Trend. While all of these Oklahoma shale plays share characteristics and collectively represent a large percentage of Oklahoma’s future oil and gas production we want to highlight the STACK play and its potential exclusively.

As mentioned, the STACK Play is an area of southeastern Oklahoma that includes oil and gas-rich shale formations such as the proven Meramac and Woodford Shale. These shale formations range in depth from 8,000 to 11,000 feet. The STACK Play is continuing to emerge and gain more prominence despite already being one of the more notable Oklahoma shale plays.

Although the South Central Oklahoma Oil Province (SCOOP) – an extension of the liquids-rich Cana Woodford shale play – remains in its infancy, the area is yielding impressive results from early wells. The Woodford shale play within the Big 4 formation has emerged as a major horizontal play in the SCOOP during the past four years. The prolific oil targets in South Central Oklahoma will continue to see “strong industry development” in the horizontal Woodford play as well as the Bromides, Big 4, Springer and Deese horizons ranging in depth from 8,000 to 16,000 feet.

The SCOOP stretches south in a 100-mile fairway from the Cana Woodford to the valley of the Red River, which separates Texas and Oklahoma. The fairway includes three of the top oil-producing counties in Oklahoma, which have combined to yield 3.2 billion barrels of oil from 60 reservoirs during the past 100 years.

Bounded on the north by the Nemaha Uplift; on the south by the Wichita Uplift; and on the east by the Arbuckle Uplift, the siliceous Woodford shale known as SCOOP is as much as 15,000 feet deep and up to 400 feet thick. What’s more, the SCOOP is surrounded by four prolific, giant oil fields – Sho-Vel-Tum, 1,700 million barrels of oil equivalent (MMBoe); Golden Trend, 1,020 MMBoe; Oklahoma City, 950 MMBoe; and Cement, 420 MMBoe.

The western half of Oklahoma lies on top of the Anadarko Basin, a huge sedimentary formation that has already yielded most of Oklahoma’s conventional oil and natural gas. In 2012, attention turned to the possibility of unlocking the basin’s unconventional resources using the same horizontal drilling and hydraulic-fracturing techniques that have prized millions of barrels of oil and condensates from the Bakken in North Dakota and the Eagle Ford in South Texas. As a result, Woodford horizontal activity shifted to Grady and Garvin counties, and the most active operators in the area included Continental, Newfield, Marathon and Eagle Rock

In a word, potential. In July, one the partnerships operators, Devon Energy Corp, reported it has encountered more success with its spacing pilot program in its STACK [Sooner Trend Anadarko Basin Canadian and Kingfisher Counties] play in Oklahoma.

The Alma spacing pilot tested five wells per section across a single interval in the upper Meramec, delivering 30-day production rates averaging 1,400 barrels of oil equivalent per day (boepd) per well. Sixty percent of this production was light oil, the Oklahoma City-based company reported in a July 18 press release. Early flowback results from the pilot indicate minimal interference between wells, suggesting potential for tighter spacing in the over-pressured oil window. The wells were drilled with 5,000-foot laterals and brought online with a 12/64-inch choke, then gradually increased to a 20/64-inch choke.

During the rest of 2016, the company will participate in several additional spacing pilots to determine to optimal approach to developing stacked-pay intervals in the Meramec, Devon said in the release.

Devon also recently brought online the Pony Express 27-1H well in the over-pressured oil window in southwest Kingfisher County, Oklahoma. The company drilled the well with a 5,000-foot lateral achieved a 30-day average rate of 2,100 boepd – including 1,500 barrels per day of oil. Devon said the well’s oil productivity is the highest of any Meramec well drilled so far in the play on a lateral foot basis.

Seeking potential growth opportunities, operators such as Marathon Oil Corp. are seeking to acquire acreage in Oklahoma’s high margin STACK basin. Recently, Marathon acquired PayRock Energy Holdings LLC for $888 million. In late 2015, Devon acquired assets in the Anadarko Basin from Felix Energy LLC for $1.9 billion to expand its STACK holdings, even as it looked to sell assets across four major shale basins to raise cash and cut debt.

The STACK play is one of the great emerging onshore North America plays, Devon Energy Corp President and CEO Dave Hager told attendees June 29 at the JP Morgan Inaugural Energy Equity Conference. The company holds 430,000 net acres in the STACK play, located mainly in Canadian, Kingfisher and Blaine counties in Oklahoma. Hager said Devon has increased its STACK production significantly, achieving first quarter net production from the STACK play of approximately 91,000 boed.

Plenty of areas in the STACK play offer returns well in excess of cost per capital, but Hager sees the Woodford and Meramec plays as the economic heart of STACK. The company has identified 5,300 gross risked drilling locations in both formations.

Continental Resources Inc. – the largest leaseholder in what used to be the nation’s premier oil play, the Bakken – called the Woodford shale “one of the thickest, best-quality resource shale reservoirs in the country.” During an analyst presentation, the Oklahoma City-based producer revealed that it had blocked up 197,000 net acres in what it dubbed the SCOOP that Continental considered prospective for liquids.

According to Richard Lane, the president and CEO of Vitruvian Exploration II, “What really got us interested in the SCOOP area was the excellent reservoir rock,” Lane said. “Our team described it as the best unconventional reservoir rock that we’ve come across. That’s after looking at a lot of plays in a lot of different basins. “It’s got the right kerogen type. It’s got great organic carbon. It has good maturity indexes. It has the condensate to go with it and the NGLs,” Lane continued, later adding the average estimated ultimate recoveries are greater than 2 MMboe. “The thickness is excellent, high porosities, good permeability, fairly silica-rich rock. All of that gives rise to a tremendous resource with about 150 to 200 Bcf per section.”

With 38,000 acres in the SCOOP area, Vitruvian estimates its reserve potential at 558 MMboe.

“The SCOOP area is just an outstanding reservoir. It’s much thicker, exceeds 400 feet in the area of our leasehold, it’s about 2,500 feet deeper. That affects the maturity. It affects the pressure and the energy that the reservoir has,” Lane said. “The IPs that we are seeing in the south part in the Scoop area are almost twice as in the Cana [Woodford] proper area. The EURs are significantly higher as well. The gas is richer, and that gives rise to the condensate and the NGLs. So overall, it’s a pretty outstanding reservoir.”