Fairway (James Lime) Field, in Henderson and Anderson counties, Texas, trapped volatile 48° oil in the Aptian age James Lime member of the Pearsall Formation. The reservoir is a large patch reef complex of varied carbonate facies that grew on a paleobathymetric high in the interior platform of the Lower Cretaceous shelf. For reservoir management purposes, the James is divided into an upper "A" zone with reef-derived skeletal grainstone and/or lagoonal facies with moldic and interparticle porosity, a "B" dense zone of non-porous reef core, and a lower "C" zone composed of uniform fine grainstone. Porosity and permeability average 12.5% and 33 mD in the "A" zone and 12.9% and <1 mD in the "C" zone, respectively, at depths of 9,800 to 10,200 ft. Total net pay averages 56 ft.
Following discovery in 1960, 157 wells were drilled on 160 acre spacing during the initial development phase. In 1963, a high pressure gas gathering system and gas plant were put into operation, and in 1965 a field-wide unit of 28,518 acres was approved, designed to conduct gas and water pressure maintenance operations. An injection project was then initiated to preserve reservoir energy and increase recovery through use of a WAG (water-alternating-gas) miscible recovery process. Additional infill drilling projects were implemented in 1971, 1980, 1991, and 2006 to optimize recovery; to date 237 wells have been drilled, including 3 recent horizontal wells targeting bypassed pay in the upper "A" and lower "C" zones. A large secondary gas saturation developed over the years as the gas recycling program was implemented. Gas sales began in 2000, and gas injection was terminated in January, 2005. OOIP in the James was calculated as 410 MMBO, of which 213 MMBO has been produced. As of Aug. 1, 2007, production was 1220 BOPD, 23,400 BWPD, 70 MMCFD, and 3360 BNGLPD. Field life is projected beyond 2015. (from Webster et al)
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