A glut of oil is slowly building around the world that should drive oil prices down decisively in the next few months, even if war breaks out in the Persian Gulf, experts say.

Prices for crude oil and gasoline may already have peaked. And unless this winter is unusually severe, even heating oil prices should not rise much more, certainly not as much as is usual in December.From a high of over $40 per 42-gallon barrel a month ago, crude oil prices should settle around $25 a barrel by spring, most experts agree, though they've remained over $30 a barrel for the past several weeks.

And there is even a real possibility that oil prices could plummet again in 1991, to $15 a barrel or below, as they did in 1986, some analysts maintain.

Even a war in the Persian Gulf region - the largest of several uncertainties overshadowing these emerging trends - that should produce only a brief interruption, probably lasting no more than a few weeks, before these fundamental trends reassert themselves.