The unitized Aline-Lambert field covers about 150 sq mi (241 sq km) in Alfalfa County, Oklahoma. Aline field produces oil from two or more porous zones in the Oswego Limestone whereas the Lambert field produces primarily gas but locally contains a thin oil column. Porous and permeable zones are discontinuous in this gas-solution drive reservoir. Gas-water and oil-water contacts in the field drop to the southeast at about 20 to 45° in the direction of regional dip. The trap is a porosity pinch-out.

The Oswego Limestone is composed of intercalated mudstones, wackestones, and packstones that range in thickness from 30 to 40 m. Maximum production in the field is from wells that penetrate a complex system of phylloid algal mounds. Distribution of the mounds is controlled by a break in slope from shallow shelf waters into a deeper water, northeast-trending embayment. Porosity values within the field range from 6 to 12%; permeabilities vary from 2 to 300 md. Porosity and permeability in non-producing wells in the area average 5% and 4 md. Five stages of cementation and partial dissolution have been recognized. Texture and isotopically light carbon values of the later stage cements suggest that they were in part formed during biochemical degradation of organics.

Initial correlation of hydrocarbons produced from the reservoir suggests that the Oswego was the source. Samples of the Oswego, juxtapositional strata, and oil and gas were processed and analyzed chromatographically for correlation studies. Organic extraction schemes involved the standard separation of alkane and aromatic fractions by column chromatography. Hydrocarbon fractions were analyzed by gas chromatography using glass capillary columns and flame ionization detection. In addition, total organic-carbon percentage in rock samples was determined by combustion and the resulting carbon dioxide was analyzed for its carbon isotopic composition. The resulting ^dgr¹³C values suggest a relation between indigenous organic matter and the later stage cements.

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