where is the most oil found in texas
Permian Basin in West Texas
Texas oil boom
The major petroleum strikes that began the rapid growth in petroleum exploration and speculation occurred in Southeast Texas, but soon reserves were found across Texas and wells were constructed in North Texas, East Texas, and the Permian Basin in West Texas. 
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Texas oil boom [SEP] Introduction
production. Some historians even define the beginning of the world's Oil Age as the beginning of this era in Texas. The major petroleum strikes that began the rapid growth in petroleum exploration and speculation occurred in Southeast Texas, but soon reserves were found across Texas and wells were constructed in North Texas, East Texas, and the Permian Basin in West Texas. Although limited reserves of oil had been struck during the 19th century, the strike at Spindletop near Beaumont in 1901 gained national attention, spurring exploration and development that continued through the 1920s and beyond. Spindletop and the Joiner strike in East Texas, at the outset of the Great Depression, were the key strikes that launched this era of change in the state.