准噶尔盆地在侏罗纪为—振荡的泛盆,形成了多期不整合,以不整合为层序边界形成的层序地层单元与油气藏的分布富集密切相关.不整合上下的低位域、高位域发育冲积扇、河流、三角洲等储集性能较好的砂砾岩,湖侵域则以厚度稳定、分布广泛的湖相泥岩为主.考虑到准噶尔盆地侏罗系不整合发育的多期性、分布的稳定性以及层序地层单元对生储盖的控制作用,建立由不整合面及不整合面上下的低位域、高位域构成的不整合复合体,多期不整合复合体与湖侵域的泥岩相互叠置形成多套生储盖组合.不整合复合体对于油气的运聚成藏起重要作用,在不整合复合体内部形成多种类型的岩性地层圈闭.不同级别的不整合复合体控制着生、储、盖组合的空间分布与富集层位,不整合复合体内部的组成单元则决定了岩性地层圈闭的类型及分布.其中,不整合复合体的低位域、高位域发育的大型冲积扇、三角洲沉积体系控制岩性圈闭的分布,而不整合复合体内的地层尖灭线控制地层圈闭的分布.%Junggar basin is an oscillated flooding basin in Jurassic, forming several unconformities, and its sequence stratigraphic units whose sequence boundaries are defined by unconformity, have a close relationship with the distribution and accumulation of reservoir. LST ( Lowstand System Tract) and HST ( Highstand System Tract) lying around the unconformity develop glutenites that possess better reservoir quality, from alluvial fan, river, and delta. TST (Transgressive System Tract) is mainly characterized by lake facies' mudstone whose thickness distribution is stable and extensive. In Junggar basin of Jurassic, considering the multiple phases of unconformity, the stability of distribution and the constraint of sequence stratigraphy to source rock, reservoir, and caprock, the authors establish the unconformity complex which is constructed by a unconformity and LST or HST existing above and below the unconformity. Several sets of source-reservoir-caprock assemblages are formed by mutual superimposition of multiple unconformity complexes and mudstone of TST. Unconformity complex plays a vital role in oil and gas migration, accumulation, and forms multiple styles of strati-graphic traps in its interior. Unconformity complexes with different levels control the distribution and enrichment of source-reservoir-caprock assemblage. Meanwhile, the interior units of unconformity complex define stratigraphic trap's style and distribution. Specifically, the large-scale alluvial fan and delta developed in the unconformity's LST and HST constrain the lithologic traps' distribution, and the thinning out lines control the stratigraphic traps.
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