William "Tex" Moncrief Jr., who was described as a "true legend" in the oil business and a "great philanthropist," died Dec. 29 at 101.

A spokeswoman for Moncrief Oil confirmed his death to The Associated Press Wednesday but could not immediately provide further details.

"He was incredibly generous, not only in Fort Worth, but around the world," state Rep. Charlie Geren told Fort Worth Star-Telegram. "The Moncrief name is all over Fort Worth. You can look at the UT Southwestern Moncrief Cancer Center, buildings at the Stock Show; he was just a very, very generous man. Fort Worth will miss him."

Coming from a family that was a pioneer in the Fort Worth oil and gas industry, Moncrief, who went by the nickname "Tex," joined the family business when he was just 10 years old and his father "Monty"—who was among the early wildcatters—discovered a 6 billion-barrel East Texas oilfield.

Continuing his father's legacy, in 2010, Moncrief Offshore LLC found an offshore field that held up to 6 trillion cubic feet of gas, according to a profile in Forbes.

Beside his notable work in oil, Moncrief was known around Texas for his generosity and donations to his community. Moncrief donated $100 million toward the University of Texas Southwestern Medical Center, first at the Moncrief Cancer Institute and later for the Monty and Tex Moncrief Medical Center, which opened in 2017, Fort Worth Star-Telegram reported.

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