In past episodes of military conflict in the Mideast, oil prices have surged amid fears of diminished supply.

But that's not the case this time around. Not much production has been interrupted in the region, and output is booming in the United States. Meanwhile, global oil demand is stagnant, thanks to sluggish growth in the world economy.

So oil prices have been tumbling, with U.S. West Texas Intermediate crude hitting a 16-month low Monday.

Jeff Rubin, former chief economist at CIBC World Markets, thinks the drop will continue.

"If crude prices end up mimicking their fossil-fuel cousin (coal), prices could be heading as low as $40 to $60 a barrel in the not-too-distant future," he wrote in a commentary obtained by MarketWatch.

November WTI futures closed at $93.04 Friday, down 50 cents. A move to $40 from that level would constitute a 57 percent drop.

Rubin noted that U.S. oil consumption has slid about 11 percent since 2007, and European consumption has slipped every year for the last five.

Other experts too say that supply-demand fundamentals cast a bearish pall over the oil market.

"The market focus has shifted from supply risks to oil glut fears to weak oil demand," Giovanni Staunovo, an analyst at UBS in Zurich, told Bloomberg. There is "strong crude oil supply in the U.S.," he said.

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