SCOOP/STACK – Evolving Play Boundaries

Abstract

The SCOOP/STACK play accounts for about 90% of rigs running in the Anadarko Basin and trails only the Permian in L48 drilling activity. With the core of the STACK play tied up by major operators, attention has turned to the emerging areas. RSEG defines the emerging areas as the Shelf, Northwest Extension and the Merge. The Shelf encompasses northeast Kingfisher and southern Major and Garfield counties. The Northwest Extension includes Woodward, Dewey, northwest Blaine and southern Major counties. The Merge area separates the STACK from the SCOOP in northern Grady and southern Canadian counties. Recent significant transactions in the emerging areas highlight the desire by E&Ps to push the boundaries of the STACK play. LNGG and Citizen Energy in the Merge contributed equal net acres to form Roan Resources, while Silver Run merged with Alta Mesa Holdings and Kingfisher Midstream to form Alta Mesa Resources.

The regional stratigraphic correlations in this study are the Late Devonian Woodford Shale and the conformably overlain Mississippian Meramec and Osage formations. The Mississippian section ranges in thickness from 250 to 1,000 feet, while the Woodford reaches up to 200 feet. The Woodford is the primary source rock for the play.

Drilling targets in the SCOOP/STACK have shifted over time. The play began in 2010 targeting the Cana Woodford Shale in the deeper parts of the basin. After a shift to the SCOOP in 2012, the first Meramec wells were tested in 2013 and today it remains the primary target. As our understanding of these areas evolves, the areal extent of the STACK continues to decrease. With the spotlight moving towards the perimeter of the play, it is important to understand the drilling, completions and geological trends stepping away from the core STACK. The Meramec calcareous shale in the STACK transitions into more of a carbonate towards the northwest and northeast onto the shelf, while localized faulting and structural activity are present the Merge. Lithology, structural geology and production are key factors in drawing the boundaries between the STACK versus emerging areas. Data analyzed in this study includes smoothed Oklahoma production, drilling, completions, well logs and AFEs This study takes a statistical approach to determine what geological, drilling and completions parameters drive well recoveries and activity levels in the core versus the various emerging areas.

AAPG Datapages/Search and Discovery Article #90323 ©2018 AAPG Annual Convention and Exhibition, Salt Lake City, Utah, May 20-23, 2018