William Alvin "Tex" Moncrief Jr., patriarch of the Moncrief Oil family and a Texas wildcatter who helped build a father-son venture into a multi-billion-dollar business over more than 70 years in the oil and gas industry, has died at age 101. A spokeswoman for Moncrief Oil confirmed his death to The Associated Press Wednesday, Dec. 29, 2021. Tex first exposed to oil business at age 10 by wildcatter father W.A. (Monty) Moncrief Sr.; witnessed dad's discovery of 6-billion-barrel oilfield in East Texas. Studied at U. of Texas - graduating in 1942 with a degree in petroleum engineering; served in Navy during WWII. Worked with father at Moncrief Oil. In 1972 acquired one-third of Wyoming's Madden Deep natural gas field; remains company's biggest asset. Owns ranches on 20,000 undeveloped acres on Barnett Shale; halting development until big players like Chesapeake and XTO Energy improve techniques. Continues drilling throughout the West.