Application of a High-Frequency Sequence Stratigraphic Framework in the 2nd Frontier, Green River Basin, Wyoming

G.L. Ford, EOG Resources, Inc, 600 17th St, Suite 1100 N, Denver, CO 80202, phone: 303-824-5592, fax: 303-824-5593, [email protected]

A high-frequency sequence stratigraphic model applied over a 700 mi² area in the Cretaceous, 2nd Frontier (Kf2) in Green River Basin, Wyoming, resulted in a 41% increase in rate of return from the year 2002 to 2003. The area includes the LaBarge Platform on the north extending up to Chimney Buttes Field, and continuous south across the southern end of the Moxa Arch. To date over 2.8 TCF of gas have been produced from the Kf2 in this region.

Approximately 2,000 wells containing raster and/or digital well-log data were used. Published core descriptions and in-house described cores help constrain the correlations and allow for calibration of facies to log characteristics. The gross stratigraphic framework encompasses two large-scale base-level rise to fall cycles. Smaller scale base-level cycles help explain and predict reservoir distribution across the area. Well-log cross sections based on this stratigraphic framework in conjunction with sand and pay maps illustrate stacking patterns, along-strike facies variations, and stratigraphic changes across the depositional profile, as well as production trends.