Huxford field, Escambia County, Alabama, was discovered in late 1982 by the Texaco 2 ATIC 35-6 well. Production was established from the upper Smackover Formation with an initial gauge of 1,070 BOPD

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and 1.1 MMCFGD. This well tested a seismically identified, sub-Jurassic topographic feature. Four unsuccessful confirmation attempts have revealed not only the difficulty in accurately predicting structural position, but also the complex facies relationships present in the upper Smackover.

Conventional cores from 5 wells reveal that in many places original depositional facies are masked by several diagenetic phases of recrystallization and dissolution. Mineralogically, the upper Smackover section is almost entirely dolomite of probably primary origin in the crestal areas, and early secondary origin on the flanks of the structure. Reservoir porosity and permeability are highly variable across the field and are controlled by several interrelated factors. Primary depositional fabric, completeness of dolomitization, and leaching of nondolomitized components were all important in creating reservoir-quality rock. Dolomitization of moderate to high-energy facies in many places resulted in porous and permeable crystalline dolomite with a sucrosic texture. In some places, incomp ete dolomitization left remnants of the primary fabric that were later leached, leaving a vuggy texture. The occurrence of nonreservoir-quality rock can be attributed to (1) nonporous dolomite of supratidal origin, (2) occlusion of pore spaces by several later generations of dolomitization, or (3) occlusion of pore spaces by anhydrite.

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