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 petroleum engineering at U. of Texas; 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.