The Nigger Creek oil field is worthy of description because it is the first commercial pool to produce Woodbine sand oil from a fault structure up-dip from the prolific Woodbine fields in the Mexia-Powell fault zone of east-central Texas. The field is located in the graben between the Mexia-Powell fault and the Balcones fault. It contains 170 productive acres, 79 producing wells, and in two years, since discovery, has produced 2,690,000 barrels of oil, or 15,823 barrels per acre, from a fine-grained soft sand having a maximum thickness of 27 feet and an average pay thickness of about 16 feet. The depth of oil sand ranges from 2,800 to 2,850 feet below the surface. The subsurface structural relief is 35 feet, and the oil-water contact was 2,360 feet below sea-level. The fa lt plane dips 43° from the surface to the Austin chalk, flattens as it passes through the chalk, and in some parts of the field it dips as low as 15° where it cuts the Woodbine sand. The surface displacement of the fault is 260 feet, and the displacement in the Woodbine sand exceeds 500 feet. The drainage area tributary to this field is limited by the Mexia and other faults located within 2 3/4 miles toward the east (down-dip). Probably upward migration along the fault zone, horizontal migration across the fault, and migration up-dip, all contributed to the accumulation in this structure. The oil has a gravity of 40° API., contains 0.27 per cent sulphur and 39.9 per cent gasoline. Although the field was overdrilled, it returned the cost of leases, development, and operating e pense plus 37 per cent profit in two years.