A Lower Pennsylvanian target that hasn’t been tested until recently with horizontal drilling could, according to Continental Resources Inc., make the state the third largest oil producer in the U.S.

The Springer shale is in south central Oklahoma and the most productive drilling is taking place in Garvin, Grady, and Stephens counties. According to Continental, the Springer Shale, termed Mississippian Goddard by some companies, is relatively shallow at 12,500 feet and ranges in thickness up to 150 feet. It is an overpressured, organic-rich, highly siliceous formation with a low percentage of clay and high porosity and permeability. The Springer lies above the Merramec and Woodford formations.

Based on data collected from 11 producers to date, estimated ultimate recovery for a well with a 4,500-foot lateral is 735,000 barrels (bbl) of oil and 1.23 billion cubic feet of gas, or 940 million barrels of oil equivalent. Completed well costs are around $9.7 million.

Continental also estimates that Springer shale wells have an estimated producing life of 11-12 years, and the formation holds up to 3.6 billion bbl of oil.

According to Tudor Pickering Holt figures, the rate of return is more than 100% in the oil fairway, based on drilling results from 11 Continental completions.

IHS Inc. reported that Continental kicked off its horizontal Springer exploration program in the region in mid-2013 with the completion of a Garvin County discovery at #1-19H Ball in Section 19-3n-4w. The well was tested in a 12/64-inch choke flowing 300 bbl of 47-degree-gravity oil and 435,000 cubic of gas with no water. It produced 111,000 barrels of oil and 167 million cubic feet (MMcf) of gas in its first nine months on stream. The average daily output at last report was 299 bbl of oil with 418,000 cubic feet of gas.

Other Continental wells of note include:

  • #1-28H Burkes, Grady County: 517 bbl of 46-degree-gravity oil and 564,000 cubic feet of gas per day
  • #1-22H Gala, Grady County: 498 bbl of 45-degree-gravity oil and 779,000 cubic feet of gas per day
  • #1-11H Anne, Grady County: 566 bbl of 43-degree-gravity oil and 1.2 MMcf/d of gas
  • #1-8H Robert Jo, Stephens County: 598 bbl of 46-degree-gravity oil and 1.31 MMcf/d of gas
  • #1-21H K.L. Fulton, Grady County: 2,122 bbl of oil equivalent per day

Some other operators have made good Springer discoveries as far back as 2008: Ward Petroleum Corp.’s #1-19 Young initially flowed 8.63 MMcf/d of gas. In 2010, JMA Energy Co.’s #1-18 Dwight in Caddo County had an initial daily flowrate of 12 MMcf of gas, with 2 bbl of condensate

Chesapeake Operating Inc.’s 2010 wells included #1-20 Horse Creek, which flowed 2.89 MMcf of gas with 65 bbl of water per day, and its #1-27 Griffin, which flowed 3.22 MMcf of gas and 17 bbl of condensate per day. In 2012 in Washita County, #1 Brown 25-10-16 flowed 6.79 MMcf of gas and #1 Capron 9-9-14 was initially tested in the Lower Cunningham member of Springer with 4.24 MMcf of gas per day after fracturing.

Continental currently holds approximately 195,000 net acres in the Springer play, with about 118,000 net acres in the oil fairway and 77,000 acres in a gas/condensate fairway. The company has three rigs working on delineation tests and five on an infill pilot project within three miles (southwest) of #1-21 K.L. Fulton. The operator’s first extended-lateral well is planned for the fourth quarter or 2014.

Continental is seeking state approval for a multi-well horizontal drilling program targeting Lower Springer shale on a southeastern Anadarko Basin unit approximately eight miles southwest of Lindsay, Oklahoma.