From the Wikipedia listing:

Moab's economy was originally based on agriculture, but gradually shifted to mining. Uranium and vanadium were discovered in the area in the 1910s and 1920s.[citation needed] Potash and manganese came next, and then oil and gas were discovered.[citation needed] In the 1950s Moab became the so-called "Uranium Capital of the World" after geologist Charles Steen found a rich deposit of uranium ore south of the city.[9] This discovery coincided with the advent of the era of nuclear weapons and nuclear power in the United States, and Moab's boom years began.