Abstract: The oil-source correlation shows that Carboniferous hydrocarbon in Beisantai area mainly came from Pingdiquan formation in Faking depression and Lacaogou formation Bogeda foreland depression.Tge aurth slope of Beisantai arch Became reservoirs only at Episode I of Yanshan movement; while the south slope at Episode I and I of Yanshan movement and Himalayan movement. How well the reservoir quality was dominantly affected by ancient weathering crust,in which upper part of leached zone was of about 100 meters thick, obv iously better than the middle and lower parts. The hydrocarbon migration was dominated by the way of lateral long or near range along the unconformity, with source bed in recent formations and reservoir bed in ancient formation, the distribution of hydrocarbon reservoirs is generally controlled by the structural trap, indicating good preserved conditions and abundant oil source supply in north slope of Beisantai area, which will be as an important target area for exploration in the future.

Key words: Junggar basin, east, Beisantai oilfield, source depression, Carboniferous, reservoir formation