Woodbine-Eagle Ford reservoirs are productive over an area of about 55 mi² (140 km²) in Kurten field. The Woodbine "C" sandstone is the most extensive reservoir and has an average net thickness of 30 ft (9 m). The "C" sandstone shows distinctive changes in rock type from south to north: (1) a cross-bedded facies consists of thin-bedded, medium-grained

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(0.28-mm) quartzose sandstones; (2) a rippled facies is thinly interbedded shale and fine-grained (0.17-mm) sandstone; and (3) a bioturbated facies is highly churned, very fine-grained (0.12-mm) sandstone. These facies result in permeabilities decreasing from an average 47 md in the south to 0.1 md in the north.

The "C" sandstone was deposited in a middle to outer shelf location, and sands were supplied by storm-driven or tidal currents from the "Harris delta" to the east. The south limit of the reservoir is controlled by a deep northeast-trending salt dome or ridge, called Hill dome. The upper Woodbine-Eagle Ford section was truncated by erosion along this trend and unconformably overlain by carbonate muds of the Austin Chalk. Sandstone facies suggest that salt uplift during deposition created a high on the sea floor, which was scoured by currents. Successively finer grained sands were deposited to the north under conditions of decreasing current flow and increasing water depths.

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