SEDIMENTARY EVOLUTION AND PROSPECTING POTENTIAL OF JURASSIC IN MINHE BASIN,WEST CHINA

A intact fault subsidence basins sedimentary sequence was formed in Jurassic in Minhe basin. Sedimentary area is gradually spread from early Jurassic to middle-late Jurassic. Lower Jurrassic is early fault subsidence lake sediment, has the characteristics of fill and level up,existed underwater fan facies coarse clast sedimentary in the basin circumference edge and lower rise and existed shore fleet lacustrine sedimentary in the basin centre. The fault subsidence lake had developed in middle Jurassic, Alluvial fan, sub-deep lacustrine-delta sedimentary sequence was formed and undergone two stage sub-lacustrine transgressive cycle. The fault subsidence lacustrine died out in late-Jurassic and damp type fan, braided stream and meander river sedimentary sequence was formed. Middle Jurassic Yaojie Formation is a lack compensation type sediment and composed of oil shale, dark shale and coal bed. The three autogeny-autoreservoir association were formed in Jurassic. Therefore,oil and gas resource is abundance in this association.