Anadarko’s Bossier Gas Play – A Sleeping Giant in a Mature Basin
By
James J. Emme, Vice
President Exploration
- Anadarko Petroleum, and
Robert W. Stancil, Chief Geologist -Anadarko Petroleum
The Bossier Sand Play in the ‘mature’ East Texas Basin has
emerged as one of the premier basin-center gas plays in the onshore U.S. For
almost 25 years, the Jurassic Bossier Sands were viewed as “bail out” zones
in wells drilled for deeper targets in the Haynesville/Cotton Valley and
Smackover Limestones. Prior to 1995, the average Bossier completion at 11,500
feet produced about 0.9 BCFG and was considered uneconomic as a primary
objective. In 1996, following a failed Cotton Valley Limestone exploration
program, Anadarko recognized the ingredients for significant gas reserves in the
Bossier Sands. Favorable geologic conditions included a petroleum system with
juxtaposed reservoir, source and seal over a broad, overpressured region.
Economic hurdles included high drilling and completion costs for relatively
low-rate gas production in “permeability-challenged” sandstones. Successive
operational/cost improvements led to economically attractive results, even in a
sub $2.00/mcf gas price environment. Average Bossier wells now take 55 days from
spud to first sales with initial rates of 3-5 MMCFD and reserves of 3 BCFG.
Exceptional wells produce up to 50 MMCFD with 10 BCFG reserves. As of August
2001, Anadarko’s East Texas Bossier production was in excess of 300 MMCFD with
proven reserves for the Dew/Mimms Creek Field of over 1.1 TCFG (“Giant
Field” status). Ultimately, the Bossier Gas Play is expected to yield multi-TCF
reserves from developing trends throughout East Texas. Anadarko’s Bossier
success can be tied to these key factors: 1) Recognition of the resource
potential, 2) Improvements in drilling/completion costs and techniques, 3)
Control of the play, and 4) Integration of midstream/marketing strategies. North
American onshore basins have many more “sleeping giants” yet to be awakened
by
innovative
explorers who recognize their potential!
AAPG Search and Discovery Article #90010©2003 AAPG Southwest Section Meeting, Fort Worth, Texas, March 1-4, 2003