(FORTUNE Magazine) – When oil prices shot up recently, geologists took another look at marginal fields that weren't worth much with crude at $18 a barrel. But Alexander Benton, 47, was way ahead of them. His company, Benton Oil & Gas in Ventura, California, had already bought a lot of properties the oil giants were anxious to unload, and has used an advanced seismic technology to sniff out more reserves. ''Their crumbs are big pieces to us,'' he says. Benton's secret: a staff crammed with veterans of top oil companies like Amoco and Shell. Staying a step ahead is second nature to Benton. Born in Russia, he fled with his family to Nazi Germany to escape Stalin. They survived bombing raids and made their way to California, where Benton toiled in a garlic factory to pay his way through college. In 1979, working for Amoco, he struck the huge Port Hudson field in Louisiana. That year he became one of the few people ever to grace the cover of Oil and Gas Journal, the industry bible, which normally sports subjects like drilling rigs. Benton is worried that higher oil prices will make it more difficult to cherry-pick properties. But so far Wall Street is gushing over him. Since Benton took the company public in March 1989, its stock has climbed to $13 a share, five times its original price.