<P> The East Texas Oil Field is a large oil and gas field in east Texas . Covering 140,000 acres (570 km) and parts of five counties, and having 30,340 historic and active oil wells, it is the second - largest oil field in the United States outside Alaska, and first in total volume of oil recovered since its discovery in 1930 . Over 5.42 billion barrels of oil have been produced from it to - date . It is a component of the Mid-Continent Oil Province, the huge region of petroleum deposits extending from Kansas to New Mexico to the Gulf of Mexico . </P> <P> The field includes parts of Gregg, western Rusk, southern Upshur, southeastern Smith, and northeastern Cherokee counties in the northeastern part of the state . Overall the field is about 45 miles (72 km) long on the north - south axis, and five miles (8 km) across . Interstate 20 cuts across the field from east to west, and the towns of Kilgore, Overton, and Gladewater are on the field . At one time, downtown Kilgore had more than 1,000 active wells clustered in a tight area, making it the densest oil development in the world . </P>

When was the east texas oil field discovered