The East Texas oil field is in the eastern part of Texas. It was discovered by random drilling by Columbus M. ("Dad") Joiner, October 3, 1930, on completion of the No. 3 Daisy Bradford.

The producing formation is the Upper Cretaceous Woodbine Sandstone. The geology of the Woodbine Sandstone in the East Texas field and related areas is comparatively simple. Regionally the field is on the western flank of the Sabine uplift, which controlled

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the deposition of the Woodbine Sandstone and the accumulation of oil in the field. The accumulation of oil is due to updip pinchout of the sandstone. This pinchout forms the eastern edge of the field. The western limit of the field is defined by an oil-water contact at a subsea depth of approximately 3,320 ft.

The Woodbine is the basal stratigraphic unit of the Upper Cretaceous. The seals above the Woodbine are the Eagle Ford Shale and the Austin Chalk. In most of the field, the Austin Chalk is in direct contact with the truncated and updip edge of the Woodbine. Beneath the reservoir sandstone is shale of the Lower Cretaceous Washita Group. Just east of the field, the Austin Chalk overlies the Washita directly.

The field has one of the largest proved oil reserves of any in the United States. This places it among the giant single oil pools of the world. The pool is 44.32 mi long (northeast-southwest) and 4.94 mi wide (east-west), and covers approximately 140,000 acres. The average net effective sandstone thickness is approximately 35 ft ranging from 0 to 102 ft. East Texas field has produced 3,860,000,000 bbl of oil to January 1, 1968, and has an estimated remaining recoverable reserve of approximately 2,000,000,000 bbl. The oil currently is selling for $3.15 per bbl in the field. The oil, gas, and liquid products produced from the field have an accumulated value of about $10,000,000,000.

In the East Texas basin there are 83 separate oil pools producing from the Woodbine, having an estimated ultimate recoverable reserve of 7,700,000,000 bbl. Seventy-six (76) percent of this reserve is in the East Texas pool.

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